Touch panel and electronic device

ABSTRACT

An electronic device includes a display device; a touch panel overlaid on the display device and including at least a predetermined side; a conductive member provided along the predetermined side; and a variable resistor having one end which is electrically connected to the conductive member and another end which is electrically connected to a predetermined potential. A resistance of the variable resistor is switchable.

This application is a continuation of pending U.S. patent applicationSer. No. 14/235,823, filed Jan. 29, 2014, which is the National Stage ofInternational Application No. PCT/JP2012/007604, filed Nov. 27, 2012,which claims priority to Japanese Application Nos. 2011-276175, filedDec. 16, 2011; 2012-074721, filed Mar. 28, 2012; 2012-085750, filed Apr.4, 2012; 2012-095879; filed Apr. 19, 2012; 2012-127290, filed on Jun. 4,2012. The entire disclosures of the above-identified applications,including the specifications, drawings and claims are incorporatedherein by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a touch panel and an electronic deviceemploying this touch panel.

BACKGROUND ART

An example of an electronic device employing a touch panel is describedin Patent Documents 1 and 2. As known widely, a touch panel is overlaidon a display device (e.g., a liquid crystal display) for displaying animage. Here, in the touch panel, an integrated construction consistingof a protection glass, a sensor (glass, film), and a touch panelcontroller is referred to as a touch panel module. Further, aconstruction consisting of a touch panel module and a display device isreferred to as a touch panel unit.

In a portable phone described in Patent Document 1, in order that when auser grasps the device in whatever manner, key operation should beachieved easily, the part of the device grasped by the user is detectedby a sensor and then the display region is shifted depending on thesituation. On the other hand, in a display apparatus with touch paneldescribed in Patent Document 2, in order that erroneous detection in thetouch panel caused by driving of the display apparatus should beavoided, each sensor electrode of the touch panel is selected one by oneand then contact of a conductor (a finger) at the position correspondingto the selected sensor electrode is judged.

PRIOR ART REFERENCES Patent Documents

-   Patent Document 1: JP-A-2010-154090-   Patent Document 2: JP-A-2011-170784

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

Meanwhile, touch panels have a problem that when a person's finger goesinto contact, dirt such as a fingerprint adheres. In this case, whenwearing a glove avoids adhesion of a fingerprint. Nevertheless, thewearing of a glove degrades the operability. These problems can beresolved by employing a touch panel of capacitive sensing type in whichoperation is achieved in a state that a finger is maintained at a heightwithin a predetermined range without the necessity of contact to thetouch panel (this approaching operation is referred to as “hoveringoperation”, hereinafter). Nevertheless, when hovering operation isperformed in a state that the device is held by the hand, the touchpanel respond to approaching of the holding hand to the touch panel.

Here, the touch panel of capacitive sensing type is described below.FIG. 42 is a diagram showing an outline configuration of a touch panelof capacitive sensing type. In this figure, a transmission electrode 101and a receiving electrode 102 are arranged apart from each other on thelower surface of a plate-shaped dielectric material 100. Then, a drivingpulse is applied on the transmission electrode 101 from a driving buffer103. When the driving pulse is applied, an electric field is generated.When a hand enters this electric field, the number of lines of electricforce between the transmission electrode 101 and the receiving electrode102 decreases. The change in the number of lines of electric forceappears as a change in the electric charge on the receiving electrode102. The change in the electric charge on the receiving electrode 102permits detection of approaching of the hand to the touch panel.

FIG. 43 is a diagram showing a situation of detecting a finger when ahand gradually approaches the touch panel. In this figure, FIG. 43( a)shows a state that the hand is apart from the electric field. FIG. 43(b) shows a finger-hovering detection state at the time that a fingerenters the electric field. FIG. 43( c) shows a finger touching detectionstate that the finger has completely entered the electric field and thentouches the touch panel. When the finger touches the touch panel with anintention of operation, this is not erroneous operation. Nevertheless,when the finger touches the touch panel at the time that the device bodyis simply held by the hand, this becomes erroneous operation.

The present invention has been devised in view of such situations. Anobject thereof is to provide: a touch panel of capacitive sensing typein which the influence of a hand to a hand-held part at the time thatthe device body is held; and an electronic device employing this touchpanel.

Means for Solving the Problem

The touch panel of the present invention is a touch panel comprising: afirst sensor panel including at least one receiving electrode; a secondsensor panel including at least one transmission electrode and overlaidon the first sensor panel; and a third sensor panel including apredetermined electrode at least a part of which overlaps with the onetransmission electrode and overlaid on the second sensor panel, whereina transmission signal identical to that for the one transmissionelectrode can be applied on the predetermined electrode. Here, at leastone transmission electrode may be provided on the surface of the firstsensor panel. Here, a receiving electrode may be provided on the rearface and a transmission electrode may be provided on the rear face ofthe second sensor panel.

According to the above-mentioned configuration, when the present touchpanel is employed in an electronic device, a situation that theelectronic device is grasped by a person can be detected.

In the above-mentioned configuration, the first sensor panel serves alsoas the third sensor panel.

According to the above-mentioned configuration, since the first sensorpanel serves also as the third sensor panel, cost reduction is achievedin the present touch panel.

In the above-mentioned configuration, the predetermined electrode can beset at a predetermined constant potential.

According to the above-mentioned configuration, the predeterminedelectrode can be set at a ground potential or a potential of Low level.

In the above-mentioned configuration, 90% or more of the area of thefirst sensor panel overlaps with the second sensor panel.

In the above-mentioned configuration, 90% or more of the area of thethird sensor panel overlaps with the second sensor panel.

In the above-mentioned configuration, the predetermined electrode isarranged in a periphery of the touch panel.

According to the above-mentioned configuration, when the present touchpanel is employed in an electronic device, a situation that theelectronic device is grasped by a person can be detected.

In the above-mentioned configuration, a part of the predeterminedelectrode is arranged between an edge of the touch panel and a pointthat internally divides the edge of the touch panel and the center intoa ratio of 1 to 4 along a line passing through the center of the touchpanel.

According to the above-mentioned configuration, when the present touchpanel is employed in an electronic device, a situation that theelectronic device is grasped by a person can be detected.

In the above-mentioned configuration, the center is the center ofgravity of the touch panel.

In the above-mentioned configuration, the predetermined electrode isarranged in an outermost periphery of a response region in the thirdsensor panel.

According to the above-mentioned configuration, when the present touchpanel is employed in an electronic device, a situation that theelectronic device is grasped by a person can be detected.

In the above-mentioned configuration, the third sensor panel isquadrangular and the predetermined electrode is arranged along at leastone side of the quadrangle.

According to the above-mentioned configuration, when the present touchpanel is employed in an electronic device, a situation that theelectronic device is grasped by a person can be detected.

In the above-mentioned configuration, the quadrangle is a rectangle andthe predetermined electrode is arranged along each of two opposite sidesof the rectangle.

According to the above-mentioned configuration, when the present touchpanel is employed in an electronic device, a situation that theelectronic device is grasped by a person can be detected.

In the above-mentioned configuration, the two opposite sides are thelonger sides.

The touch panel unit of the present invention is a touch panel unitcomprising: a touch panel module including a protection glass, a touchpanel described above, and a board on which a touch panel controller ismounted; and a display device overlaid on the touch panel module.

According to the above-mentioned configuration, when the present touchpanel unit is employed in an electronic device, a situation that theelectronic device is grasped by a person can be detected.

The electronic device of the present invention is an electronic deviceincluding a touch panel unit described above, wherein when in a statethat a transmission signal identical to that for the one transmissionelectrode is applied on the predetermined electrode, a predeterminedcondition is detected, application of the transmission signal identicalto that for the one transmission electrode onto the predeterminedelectrode is stopped.

According to the above-mentioned configuration, a situation that thepresent electronic device is grasped by a person can be detected.

In the above-mentioned configuration, when in a state that atransmission signal identical to that for the one transmission electrodeis applied on the predetermined electrode, a predetermined condition isdetected, the predetermined electrode is set at a predetermined constantpotential.

In the above-mentioned configuration, the predetermined condition is todetect grasping by a person.

In the above-mentioned configuration, in a state that a transmissionsignal identical to that for the one transmission electrode is appliedon the predetermined electrode, the display device performspredetermined display. Further, in a state that a transmission signalidentical to that for the one transmission electrode is not applied onthe predetermined electrode, the display device does not perform thepredetermined display.

The above-mentioned configuration permits visual recognition of a statethat a situation that the present electronic device is grasped by aperson is detectable.

The transmission signal application method of the present invention is atransmission signal application method employable in a touch panelincluding: a first sensor panel including at least one receivingelectrode; a second sensor panel including at least one transmissionelectrode and overlaid on the first sensor panel; and a third sensorpanel including a predetermined electrode at least a part of whichoverlaps with the one transmission electrode and overlaid on the secondsensor panel, wherein a transmission signal identical to that for theone transmission electrode can be applied on the predeterminedelectrode.

According to the above-mentioned method, when the present touch panel isemployed in an electronic device, a situation that the electronic deviceis grasped by a person can be detected.

The touch panel of the present invention is a touch panel comprising atleast one sensor panel including: a first surface including at least onereceiving electrode; a second surface including at least onetransmission electrode and overlaid on the first surface; and a thirdsurface including a predetermined electrode at least a part of whichoverlaps with the one transmission electrode and overlaid on the secondsurface, wherein a transmission signal identical to that for the onetransmission electrode can be applied on the predetermined electrode.

According to the above-mentioned configuration, when the present touchpanel is employed in an electronic device, a situation that theelectronic device is grasped by a person can be detected.

In the above-mentioned configuration, the first surface and the thirdsurface are an identical surface.

According to the above-mentioned configuration, the sensor panel for thefirst surface and the sensor panel for the third surface need not beprovided independently. This permits cost reduction of the present touchpanel.

The transmission signal application method of the present invention is atransmission signal application method employable in a touch panelprovided with at least one sensor panel including: a first surfaceincluding at least one receiving electrode; a second surface includingat least one transmission electrode and overlaid on the first surface;and a third surface including a predetermined electrode at least a partof which overlaps with the one transmission electrode and overlaid onthe second surface, wherein a transmission signal identical to that forthe one transmission electrode can be applied on the predeterminedelectrode.

According to the above-mentioned method, when the present touch panel isemployed in an electronic device, a situation that the electronic deviceis grasped by a person can be detected.

The electronic device of the present invention is an electronic devicecomprising: a display device; and a touch panel overlaid on the displaydevice, wherein when an instructing body is not in contact with thetouch panel, the touch panel can detect at least a distance between theinstructing body and the touch panel, and wherein the display deviceperforms display in a manner of switching at least three kinds ofcharacters in predetermined order in response to an increase in thedistance.

According to the above-mentioned configuration, in response to anincrease in the distance between the instructing body (e.g., a fingerand a pen tip) and the touch panel, display is performed in a manner ofswitching at least three kinds of characters in predetermined order.Thus, a desired character can be selected by easy operation and henceoperability improvement in character selection is achieved.

In the above-mentioned configuration, the display device performsdisplay in a manner of switching the three kinds of characters in orderreverse to the predetermined order in response to a decrease in thedistance.

According to the above-mentioned configuration, a desired character canbe selected by bringing the instructing body close to or apart from thetouch panel. This improves operability in character selection.

In the above-mentioned configuration, the display device includes apredetermined display region. Then, when the instructing body is not incontact with the touch panel, the touch panel can detect at least adistance between the instructing body and the touch panel andcoordinates of the instructing body on the touch panel surface. Further,when the instructing body is not in contact with the touch panel and thecoordinates correspond to an inside of the predetermined display region,in response to an increase in the distance, the display device performsdisplay in a manner of switching at least three kinds of characters inpredetermined order.

According to the above-mentioned configuration, when the instructingbody is not in contact with the touch panel and the coordinates of theinstructing body on the touch panel surface correspond to the inside ofthe predetermined display region, in response to an increase in thedistance between the instructing body and the touch panel, display isperformed in a manner of switching at least three kinds of characters inpredetermined order. Thus, a desired character can be selected by easyoperation and hence operability improvement in character selection isachieved.

In the above-mentioned configuration, after display is performed in amanner of switching the character, when the coordinates exit thepredetermined display region, predetermined operation is performed.

According to the above-mentioned configuration, operation relevant toswitching of the character is allowed.

In the above-mentioned configuration, the predetermined operation isoperation of selecting a character displayed in a manner of beingswitched.

According to the above-mentioned configuration, as operation relevant toswitching of the character, selection of a character is allowed.

In the above-mentioned configuration, the predetermined display regionis adopted as a first display region, the display device includes asecond display region, the first display region is provided in a numberof at least one, the second display region is provided in a number of atleast two, and the two second display regions respectively performdisplay in a manner of switching the at least three kinds of charactersin predetermined order.

According to the above-mentioned configuration, in each of at least twodisplay regions, display is performed in a manner of switching at leastthree kinds of characters in predetermined order. Thus, a desiredcharacter can be selected by easy operation and hence operabilityimprovement in character selection is achieved.

In the above-mentioned configuration, when the coordinates fall at leastwithin the first display region, in response to an increase in thedistance, the display device performs display in a manner of switchingat least three kinds of characters in predetermined order. Further, whenthe coordinates exit the first display region and/or fall within thesecond display region, even when the distance varies, the display devicedoes not perform display in a manner of switching the character.

According to the above-mentioned configuration, when the coordinates ofthe instructing body on the touch panel surface exit the first displayregion or alternatively enter the second display region, even in a casethat a change occurs in the distance with the instructing body, displaywith changing the character is not performed. This reduces erroneousoperation and improves operability in character selection.

In the above-mentioned configuration, when the coordinates fall at leastwithin the first display region, in response to an increase in thedistance, the display device performs display in a manner of switchingat least three kinds of characters in predetermined order. Further, whenthe coordinates fall outside the first display region and/or fall withinthe second display region, the second display region continuesdisplaying the displayed character and does not switch the charactereven when the distance varies.

According to the above-mentioned configuration, when the coordinates ofthe instructing body on the touch panel surface exit the first displayregion or alternatively enter the second display region, the characterdisplayed in the second display region is displayed continuously. Thatis, even in a case that a change occurs in the distance with theinstructing body, the character is not switched. This reduces erroneousoperation and improves operability in character selection.

In the above-mentioned configuration, the touch panel can detect contactof the instructing body and, in a case that the instructing body goesinto contact with the touch panel, coordinates of the instructing bodyon the touch panel surface. Further, when the character is displayedcontinuously and the touch panel detects at least contact, the characterdisplayed continuously in the second display region corresponding to thecoordinates of the contact is regarded as being confirmed.

According to the above-mentioned configuration, in a case that thecharacter is displayed continuously in the second display region, whencontact to the touch panel by the instructing body is detected, thecharacter displayed continuously in the second display region isconfirmed. Thus, the selected character can be confirmed easily andhence operability improvement in character selection is achieved.

In the above-mentioned configuration, the second display regioncorresponding to the coordinates of the contact indicates the seconddisplay region closer to the coordinates of the contact.

In the above-mentioned configuration, the second display regioncorresponding to the coordinates of the contact indicates is the seconddisplay region that encompasses the coordinates of the contact.

In the above-mentioned configuration, the display device includes aninput region. Then, in the input region, the selected character isinputted.

In the above-mentioned configuration, the three kinds of characters andthe predetermined order are successive three kinds and their orderselected from at least alphabets consisting of “A”, “B”, “C”, “D”, “E”,“F”, “G”, “H”, “I”, “J”, “K”, “L”, “M”, “N”, “O”, “P”, “Q”, “R”, “S”,“T”, “U”, “V”, “W”, “X”, “Y”, “Z”, “A”, “B”.

In the above-mentioned configuration, the three kinds of characters andthe predetermined order are successive three kinds and their orderselected from at least numeric characters consisting of “1”, “2”, “3”,“4”, “5”, “6”, “7”, “8”, “9”, “0”, “1”, “2” or alternatively “0”, “1”,“2”, “3”, “4”, “5”, “6”, “7”, “8”, “9”, “10”, “11”.

In the above-mentioned configuration, the three kinds of characters andthe predetermined order are successive three kinds and their orderselected from at least Japanese characters consisting of “a”, “ka”,“sa”, “ta”, “na”, “ha”, “ma”, “ya”, “ra”, “wa”, “n”, “a”, “ka” oralternatively “i”, “ki”, “shi”, “chi”, “ni”, “hi”, “mi”, “i”, “ri”,“wi”, “i”, “ki”.

In the above-mentioned configuration, the second display regions areprovided in a number of at least five.

In the above-mentioned configuration, a housing is provided and thedisplay device is arranged in the housing.

In the above-mentioned configuration, the touch panel is arranged on theouter side of the housing relative to the display device.

The character display method of the present invention is a characterdisplay method employable in an electronic device including a displaydevice and a touch panel overlaid on the display device, wherein inresponse to an increase in a distance between the instructing body andthe touch panel, display is performed in a manner of switching at leastthree kinds of characters in predetermined order.

According to the above-mentioned method, in response to an increase inthe distance between the instructing body (e.g., a finger and a pen tip)and the touch panel, display is performed in a manner of switching atleast three kinds of characters in predetermined order. Thus, a desiredcharacter can be selected by easy operation and hence operabilityimprovement in character selection is achieved.

The electronic device of the present invention is an electronic devicecomprising: a sensor capable of detecting grasping by a person; and avibration unit, wherein when the sensor detects grasping, the vibrationunit is allowed to vibrate, and wherein when the sensor does not detectgrasping, the vibration unit does not vibrate.

According to the above-mentioned configuration, when a situation thatthe user grasps the electronic device is detected, the vibration unit isbrought into a state that vibration is allowed. When a situation thatthe user grasps the electronic device is not detected, the vibrationunit is prevented from vibrating. Thus, in a case that the user graspsand operates the electronic device, when operation is performed,vibration is generated so as to cause the user to recognize theoperation. Further, when the electronic device is operated in a state ofbeing placed on a desk or the like, vibration is not generated even whenoperation is performed. This avoids a situation that recognition at thetime of operation becomes difficult. That is, when the electronic deviceis operated in a state of being placed on a desk or the like, vibrationcould be generated on the desk or the like and hence recognition at thetime of operation could become difficult. Thus, in such a case, in acase that vibration is prevented even when operation is performed, thesituation that recognition at the time of operation becomes difficult isavoided.

In the above-mentioned configuration, a touch panel is provided. Then,when contact is detected in the touch panel, the vibration unit vibratesfor a predetermined time.

According to the above-mentioned configuration, when contact to thetouch panel is detected, the vibration unit is caused to vibrate for apredetermined time. This allows the user to reliably recognize thatoperation to the touch panel has been performed.

In the above-mentioned configuration, the sensor is the touch panel.

In the above-mentioned configuration, the vibration unit is at least oneof a vibrator, a piezo actuator, and a vibration actuator.

In the above-mentioned configuration, a display device is provided.Then, when the sensor detects grasping and contact is detected in thetouch panel, the vibration unit vibrates for a predetermined time.Further, when the sensor does not detect grasping and contact isdetected in the touch panel, the vibration unit does not vibrate and thedisplay device performs predetermined display.

According to the above-mentioned configuration, when a situation thatthe user grasps the electronic device is detected and contact to thetouch panel is detected, the vibration unit is caused to vibrate for apredetermined time. Further, when a situation that the user grasps theelectronic device is not detected and contact to the touch panel isdetected, the vibration unit is not caused to vibrate and the displaydevice is caused to perform predetermined display. Thus, when the usergrasps the electronic device and performs operation to the touch panel,vibration is generated so as to cause the user to recognize theoperation. Further, when the electronic device is placed and operated ona desk or the like, the display device performs predetermined display soas to cause the user to recognize the operation.

In the above-mentioned configuration, a display device is provided.Then, when the sensor detects grasping and contact is detected in thetouch panel, the vibration unit vibrates for a predetermined time.Further, when the sensor does not detect grasping and contact isdetected in the touch panel, the vibration unit does not vibrate and thedisplay device performs predetermined display for a predetermined time.

According to the above-mentioned configuration, in a case that theelectronic device is placed and operated on a desk or the like, whencontact to the touch panel is detected, predetermined display in thedisplay device is performed for a predetermined time. Thus, even in acase that the electronic device is placed and operated on a desk or thelike, the user is caused to reliably recognize the operation to thetouch panel.

In the above-mentioned configuration, a sound emission unit is provided.Then, when the sensor detects grasping and contact is detected in thetouch panel, the vibration unit vibrates for a predetermined time.Further, when the sensor does not detect grasping and contact isdetected in the touch panel, the vibration unit does not vibrate and thesound emission unit emits predetermined sound.

According to the above-mentioned configuration, in a case that theelectronic device is placed and operated on a desk or the like, whencontact to the touch panel is detected, the sound emission unit emitspredetermined sound. Thus, even in a case that the electronic device isplaced and operated on a desk or the like, the user is caused toreliably recognize the operation to the touch panel.

In the above-mentioned configuration, a sound emission unit is provided.Then, when the sensor detects grasping and contact is detected in thetouch panel, the vibration unit vibrates for a predetermined time.Further, when the sensor does not detect grasping and contact isdetected in the touch panel, the vibration unit does not vibrate and thesound emission unit emits predetermined sound for a predetermined time.

According to the above-mentioned configuration, in a case that theelectronic device is placed and operated on a desk or the like, whencontact to the touch panel is detected, the sound emission unit emitspredetermined sound for a predetermined time. Thus, even in a case thatthe electronic device is placed and operated on a desk or the like, theuser is caused to reliably recognize the operation to the touch panel.

The vibration control method of the present invention is a vibrationcontrol method employable in an electronic device including: a sensorcapable of detecting grasping by a person; and a vibration unit, whereinwhen the sensor detects grasping, the vibration unit is allowed tovibrate, and wherein when the sensor does not detect grasping, thevibration unit does not vibrate.

According to the above-mentioned method, when a situation that the usergrasps the electronic device is detected, the vibration unit is broughtinto a state that vibration is allowed. When a situation that the usergrasps the electronic device is not detected, the vibration unit isprevented from vibrating. Thus, in a case that the user grasps andoperates the electronic device, when operation is performed, vibrationis generated so as to cause the user to recognize the operation.Further, when the electronic device is operated in a state of beingplaced on a desk or the like, vibration is not generated even whenoperation is performed. This avoids a situation that recognition at thetime of operation becomes difficult. That is, when the electronic deviceis operated in a state of being placed on a desk or the like, vibrationcould be generated on the desk or the like and hence recognition at thetime of operation could become difficult. Thus, in such a case, in acase that vibration is prevented even when operation is performed, thesituation that recognition at the time of operation becomes difficult isavoided.

The electronic device of the present invention is an electronic devicecomprising: a display device; a touch panel overlaid on the displaydevice and including at least a predetermined side; a conductive memberprovided along the predetermined side; and a variable resistor whose oneend is electrically connected to the conductive member and whose theother end is electrically connected to a predetermined potential,wherein a resistance of the variable resistor is switchable.

According to the above-mentioned configuration, the part of the touchpanel where the conductive member is provided and its surroundings areshielded. Then, the degree of this shielding varies depending on theresistance of the variable resistor, and increases with decreasingresistance so that the sensitivity in the conductive member peripherydecreases in the touch panel. Thus, when the part of the touch panelwhere the conductive member is provided is grasped with the hand, theresistance of the variable resistor is reduced so that the influencefrom the hand (i.e., malfunction caused by a response of the touchpanel) can be suppressed.

In the above-mentioned configuration, the predetermined side is adoptedas a first side, the conductive member is adopted as a first conductivemember, the touch panel includes a second side, and the variableresistor is adopted as a first variable resistor. Further, theelectronic device is provided with a second conductive member providedalong the second side and with a second variable resistor whose one endis electrically connected to the second conductive member and whose theother end is electrically connected to the predetermined potential.Furthermore, a resistance of the first variable resistor and aresistance of the second variable resistor are switchable.

According to the above-mentioned configuration, the part of the touchpanel where the first conductive member is provided and its surroundingsand the part where the second conductive member is provided and itssurroundings can be shielded respectively. Then, the degree of shieldingin the part where the first conductive member is provided and itssurroundings varies depending on the resistance of the first variableresistor and the degree of shielding in the part where the secondconductive member is provided and its surroundings varies depending onthe resistance of the second variable resistor. Then, the degree of theshielding increases with decreasing resistance of each of the first andthe second variable resistors so that the sensitivity decreases in eachpart of the touch panel where the first or the second conductive memberis provided and the surroundings of each part. Thus, when the part ofthe touch panel where the first or the second conductive member isprovided is grasped with the hand, the resistance of each of the firstand the second variable resistors is reduced so that the influence fromthe hand can be suppressed.

In the above-mentioned configuration, the first side and the second sideare opposite to each other.

In the above-mentioned configuration, the touch panel is quadrangularand the first side and the second side are sides opposite to each otherin the quadrangle.

In the above-mentioned configuration, the touch panel is rectangular andthe first side and the second side are the longer sides opposite to eachother in the rectangle.

In the above-mentioned configuration, the resistance of the firstvariable resistor and/or the resistance of the second variable resistorare switched depending on an operation state.

According to the above-mentioned configuration, for example, in a casethat the electronic device is grasped with the left hand and operatedwith the right hand, when the resistance of each of the first and thesecond variable resistors is switched to a value of middle magnitude,the influence to the touch panel caused by grasping the device body witha single hand can be suppressed. Further, in a case that the electronicdevice is grasped with the left hand and the touch panel is operatedwith the left thumb or the like, when the resistance of the variableresistor connected to the conductive member on the left hand side isswitched to a small value, the influence to the touch panel caused bythe left thumb can be suppressed. Further, in a case that the electronicdevice is grasped with the right hand and the touch panel is operatedwith the right thumb or the like, when the resistance of the variableresistor connected to the conductive member on the right hand side isswitched to a small value, the influence to the touch panel caused bythe right thumb can be suppressed.

In the above-mentioned configuration, in a predetermined operationstate, the resistance of the first variable resistor is set to be afirst resistance and the resistance of the second variable resistor isset to be a second resistance greater than the first resistance.

According to the above-mentioned configuration, when the electronicdevice is grasped with a single hand (the left hand or the right hand)and the touch panel is operated with the thumb or the like of thegrasping hand, the influence to the touch panel caused by the thumb orthe like can be suppressed.

In the above-mentioned configuration, the predetermined operation stateis adopted as a first operation state. Then, in a second operationstate, the resistance of the first variable resistor is set to be thesecond resistance and the resistance of the second variable resistor isset to be the first resistance.

According to the above-mentioned configuration, in response to theswitching of the operation state between the first operation state andthe second operation state, the resistances of the first variableresistor and the second variable resistor are changed and hence theinfluence to the touch panel can be suppressed in whichever of the firstand the second operation states.

In the above-mentioned configuration, the predetermined operation stateis adopted as a first operation state. Then, in a second operationstate, the resistance of the first variable resistor is set to be athird resistance and the resistance of the second variable resistor isset to be a fourth resistance smaller than the third resistance.

According to the above-mentioned configuration, when the electronicdevice is grasped with a single hand (the left hand or the right hand)and the touch panel is operated with the thumb or the like of thegrasping hand, the influence to the touch panel caused by the thumb orthe like can be suppressed.

In the above-mentioned configuration, the predetermined operation stateis adopted as a first operation state. Then, in a third operation state,the resistance of the first variable resistor and the resistance of thesecond variable resistor are set to be the second resistance.

According to the above-mentioned configuration, when the electronicdevice is grasped with a single hand (the left hand or the right hand)and the touch panel is operated with the thumb or the like of the otherhand of the grasping hand, the influence to the touch panel can besuppressed.

In the above-mentioned configuration, the predetermined operation stateis adopted as a first operation state. Then, in a third operation state,the resistance of the first variable resistor is set to be a fifthresistance and the resistance of the second variable resistor is set tobe a sixth resistance that is a predetermined magnification of the fifthresistance.

According to the above-mentioned configuration, when the electronicdevice is grasped with a single hand (the left hand or the right hand)and the touch panel is operated with the thumb or the like of the otherhand of the grasping hand, the influence to the touch panel can besuppressed.

In the above-mentioned configuration, in a fourth operation state, theresistance of the first variable resistor is set to be a seventhresistance greater than at least the second resistance and theresistance of the second variable resistor is set to be the seventhresistance.

According to the above-mentioned configuration, the degree of theshielding by the first and the second conductive members is reduced andhence the sensitivity increases in the part where the first and thesecond conductive members of the touch panel are provided and itsperiphery. This realizes operability improvement in a placed state ofthe electronic device.

In the above-mentioned configuration, in a fourth operation state, theresistance of the first variable resistor is set to be a seventhresistance greater than at least the second resistance and theresistance of the second variable resistor is set to be an eighthresistance greater than at least the second resistance.

According to the above-mentioned configuration, the degree of theshielding by the first and the second conductive members is reduced andhence the sensitivity increases in the part where the first and thesecond conductive members of the touch panel are provided and itsperiphery. This realizes operability improvement in a placed state ofthe electronic device.

In the above-mentioned configuration, the operation state is detected onthe basis of output from the touch panel.

According to the above-mentioned configuration, the operation state canbe detected on the basis of the output from the touch panel.

In the above-mentioned configuration, an acceleration sensor fordetecting an attitude of the electronic device body is further providedand the operation state is detected on the basis of output from theacceleration sensor.

According to the above-mentioned configuration, the operation state canbe detected on the basis of the output from the acceleration sensor.

In the above-mentioned configuration, the predetermined potential is aground potential.

The resistance switching method of the present invention is a resistanceswitching method employable in an electronic device including: a displaydevice; a touch panel overlaid on the display device and including atleast a predetermined side; a conductive member provided along thepredetermined side; and a variable resistor whose one end iselectrically connected to the conductive member and whose the other endis electrically connected to a predetermined potential, wherein aresistance of the variable resistor is switchable.

According to the above-mentioned method, the part of the touch panelwhere the conductive member is provided and its surroundings areshielded. Then, the degree of this shielding varies depending on theresistance of the variable resistor, and increases with decreasingresistance so that the sensitivity in the conductive member peripherydecreases in the touch panel. Thus, when the part of the touch panelwhere the conductive member is provided is grasped with the hand, theresistance of the variable resistor is reduced so that the influencefrom the hand (i.e., malfunction caused by a response of the touchpanel) can be suppressed.

The electronic device of the present invention is an electronic devicecomprising: a display device; and a touch panel overlaid on the displaydevice and capable of detecting a distance with an instructing body,wherein when in a predetermined region of the display device, thedistance becomes greater than or equal to 0 and smaller than or equal toa predetermined value and, after that, the distance between the touchpanel and the instructing body becomes greater than the predeterminedvalue, in response to a change in the distance between the touch paneland the instructing body, the display device changes and displaysinformation relevant to the predetermined region.

According to the above-mentioned configuration, in response to a changein the distance between the touch panel and the instructing body, theinformation relevant to the predetermined region of the display deviceis changed and displayed. Thus, desired information can be selectedeasily and hence operability improvement in character input is achieved.

In the above-mentioned configuration, in response to an increase in thedistance between the touch panel and the instructing body, the displaydevice changes and displays information relevant to the predeterminedregion.

According to the above-mentioned configuration, in response to anincrease in the distance between the touch panel and the instructingbody, the information relevant to the predetermined region of thedisplay device is changed and displayed. Thus, desired information canbe selected easily and hence operability improvement in character inputis achieved.

In the above-mentioned configuration, in response to an increase in thedistance between the touch panel and the instructing body, the displaydevice enlarges and displays information relevant to the predeterminedregion.

According to the above-mentioned configuration, in response to anincrease in the distance between the touch panel and the instructingbody, the information relevant to the predetermined region of thedisplay device is enlarged and displayed. Thus, information in a desiredsize can be selected easily and hence operability improvement incharacter input is achieved.

In the above-mentioned configuration, the predetermined value is 0.

In the above-mentioned configuration, the display device is capable ofdisplaying at least one icon and the predetermined region corresponds tothe icon.

According to the above-mentioned configuration, the predetermined regionof the display device is brought into correspondence to the icon. Thus,the predetermined region becomes clear and hence operability improvementin character input is achieved.

In the above-mentioned configuration, the icon is a cursor key andinformation relevant to the cursor key is an input character candidatecorresponding to the cursor key.

According to the above-mentioned configuration, the icon is adopted asthe cursor key and the information relevant to the cursor key isregarded as the input character candidate corresponding to the cursorkey. Thus, operability improvement in character input is achieved.

In the above-mentioned configuration, the cursor key displays the kindof input character.

According to the above-mentioned configuration, a kana character, analphabetical character, a numeric character, and the like are displayedas the kind of input character. Thus, operability improvement incharacter input is achieved.

In the above-mentioned configuration, the input character candidate isdisplayed in a form of ten keys.

According to the above-mentioned configuration, the input charactercandidate is displayed in the form of ten keys. Thus, operabilityimprovement in character input is achieved.

In the above-mentioned configuration, the size of the input charactercandidate is fixed when the instructing body is moved in a horizontaldirection.

According to the above-mentioned configuration, when the instructingbody is moved in a horizontal direction, the size of the input charactercandidate is fixed. Thus, operability improvement in character input isachieved.

In the above-mentioned configuration, the predetermined value is adoptedas a first predetermined value and the display device includes an inputcharacter display region for displaying a character inputted therein.Then, in the input character candidate whose size has been fixed, whenthe distance becomes greater than or equal to 0 and smaller than orequal to the second predetermined value, the input character displayregion displays a character serving as the input character candidate forwhich the distance has become greater than or equal to 0 and smallerthan or equal to the second predetermined value.

According to the above-mentioned configuration, in addition to thepredetermined region for displaying the input character candidate, thedisplay device includes the input character display region fordisplaying the inputted character. Thus, sight line movement forcharacter input and displayed character check is reduced and henceoperability improvement in character input is achieved.

In the above-mentioned configuration, the input character display regiondisplays a character string containing a character serving as the inputcharacter candidate for which the distance has become greater than orequal to 0 and smaller than or equal to the second predetermined value.Then, in the character string, when the distance becomes greater than orequal to 0 and smaller than or equal to the second predetermined value,the input character display region displays a character of the characterstring for which the distance has become greater than or equal to 0 andsmaller than or equal to the second predetermined value.

According to the above-mentioned configuration, a character string isdisplayed that contains a character serving as the input charactercandidate for which the distance between the touch panel and theinstructing body has become greater than or equal to 0 and smaller thanor equal to the second predetermined value. After that, when thedistance between the touch panel and the instructing body has againbecome greater than or equal to 0 and smaller than or equal to thesecond predetermined value, the character of a character string forwhich the distance has become greater than or equal to 0 and smallerthan or equal to the second predetermined value is displayed. Thus, adesired character can be selected easily from the character string andhence operability improvement in character input is achieved.

In the above-mentioned configuration, the second predetermined value isequal to the first predetermined value or alternatively 0.

The display method of the present invention is a display methodemployable in an electronic device including: a display device; and atouch panel overlaid on the display device and capable of detecting adistance with an instructing body, wherein when in a predeterminedregion of the display device, the distance becomes greater than or equalto 0 and smaller than or equal to a predetermined value and, after that,the distance between the touch panel and the instructing body becomesgreater than the predetermined value, in response to a change in thedistance between the touch panel and the instructing body, the displaydevice changes and displays information relevant to the predeterminedregion.

According to the above-mentioned method, in response to a change in thedistance between the touch panel and the instructing body, theinformation relevant to the predetermined region of the display deviceis changed and displayed. Thus, desired information can be selectedeasily and hence operability improvement in character input is achieved.

In the above-mentioned method, the predetermined value is 0.

Effect of the Invention

According to the present invention, in a touch panel of capacitivesensing type, the influence of a hand to a hand-held part at the timethat the device body is held is suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 Perspective view showing an outline of an electronic deviceaccording to Embodiment 1 of the present invention

FIG. 2 Block diagram showing an outline configuration of an electronicdevice of FIG. 1

FIG. 3 Sectional view of an electronic device of FIG. 1 taken along lineA-A

FIG. 4 Perspective view showing arrangement relation between a coverpanel, a receiving sensor panel, a transmission sensor panel, and aLiquid crystal display unit in a Touch panel unit of an electronicdevice of FIG. 1

FIG. 5 Plan view diagram showing a receiving sensor panel of a Touchpanel unit of an electronic device of FIG. 1

FIG. 6 Plan view diagram showing a transmission sensor panel of a Touchpanel unit of an electronic device of FIG. 1

FIG. 7 Plan view diagram showing a state that a receiving sensor paneland a transmission sensor panel of an electronic device of FIG. 1 areoverlaid with each other

FIG. 8 Timing chart showing operation of a touch panel controller of anelectronic device of FIG. 1

FIG. 9 Diagram used for describing the arrangement position of atransmission electrode in a receiving sensor panel of an electronicdevice of FIG. 1

FIG. 10( a) and FIG. 10( b): Diagrams showing a change in display of aLiquid crystal display unit at not-yet-detected time that approaching ofa person's hand is not detected and at the time that approaching of aperson's hand is detected in an electronic device of FIG. 1

FIG. 11 Flow chart used for describing operation of a touch panelcontroller of an electronic device of FIG. 1

FIG. 12 Timing chart showing operation of a touch panel controller in anapplication example of an electronic device of FIG. 1

FIG. 13 Front view showing an outline of an electronic device accordingto Embodiment 2 of the present invention

FIG. 14 Block diagram showing an outline configuration of an electronicdevice of FIG. 13

FIG. 15 Diagram schematically showing alphabetical character inputoperation in an electronic device of FIG. 13

FIG. 16( a) to FIG. 16( c): Diagrams schematically showing alphabeticalcharacter input operation in an electronic device of FIG. 13

FIG. 17 Diagram schematically showing kana character input operation inan electronic device of FIG. 13

FIG. 18 FIG. 18( a) to FIG. 18( c): Diagrams schematically showing kanacharacter input operation in an electronic device of FIG. 13

FIG. 19 Diagram showing positional relation between a fingertip and aTouch panel unit at the time of character input in an electronic deviceof FIG. 13

FIG. 20 Diagram showing a time-dependent change in the distance betweena fingertip and a Touch panel unit at the time of character input in anelectronic device of FIG. 13

FIG. 21 Flow chart showing character input processing of an electronicdevice of FIG. 13

FIG. 22 Block diagram showing an outline configuration of an electronicdevice according to Embodiment 3 of the present invention

FIG. 23 Diagram showing a situation that an electronic device of FIG. 22is held and operated with the hand

FIG. 24 Diagram showing a situation that an electronic device of FIG. 22is placed and operated on a desk

FIG. 25 Sectional view showing an example of arrangement of a vibrationfeedback element in an electronic device of FIG. 22

FIG. 26 Flow chart showing operation notification processing of anelectronic device of FIG. 22

FIG. 27 Block diagram showing an outline configuration of an electronicdevice according to Embodiment 4 of the present invention

FIG. 28 Perspective view showing the fixing positions of two shieldgrounds and connection between the two shield grounds and variableresistors in an electronic device of FIG. 27

FIG. 29 Diagram showing a cross section of a part where a shield groundis arranged in a housing of an electronic device of FIG. 27

FIG. 30 Diagram showing an example of a method of detecting theholding-hand state of an electronic device of FIG. 27

FIG. 31 Diagram showing an example of the holding-hand state (i.e., thegrasping state) and the resistance of each variable resistor in anelectronic device of FIG. 27

FIG. 32 Flow chart showing holding-hand detection processing of anelectronic device of FIG. 27

FIG. 33 Block diagram showing an outline configuration of an electronicdevice which detects a holding-hand state by using an accelerationsensor

FIG. 34 Front view showing an outline of an electronic device accordingto Embodiment 5 of the present invention

FIG. 35 Block diagram showing an outline configuration of an electronicdevice of FIG. 34

FIG. 36 Diagram showing a method of detecting a finger in a touch panelcontroller of an electronic device of FIG. 34

FIG. 37 Diagram showing a time-dependent change in the distance betweena finger and a Touch panel unit in a method of detecting a finger ofFIG. 36

FIG. 38 Diagram showing operation from selection of the kind of inputcharacter to selection of a ten-key size in an electronic device of FIG.34

FIG. 39 Flow chart showing a procedure of selection operation for thekind of input character and selection operation for a ten-key size in anelectronic device of FIG. 34

FIG. 40 Diagram showing operation from selection of the kind of inputcharacter to character input in an electronic device of FIG. 34

FIG. 41 Flow chart showing character input processing of an electronicdevice of FIG. 34

FIG. 42 Diagram showing a touch panel of capacitive sensing type

FIG. 43 Diagram showing a situation of detecting a finger when a handgradually approaches a touch panel

FIG. 44 Diagram showing an example of a mail screen in an electronicdevice provided with ten keys

BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments for implementing the present invention aredescribed below with reference to the drawings.

Embodiment 1

FIG. 1 is a perspective view showing an outline of an electronic deviceaccording to Embodiment 1 of the present invention. In this figure, theelectronic device 1 according to the present embodiment is a portablewireless device referred to as a smart phone, in which a receiver 3 isprovided in an upper part on the front face side of a housing 2 formedin a quadrangular shape, and a touch panel module 6 of capacitivesensing type is provided under the receiver 3. Further, three functionbuttons 7-1 to 7-3 are provided under the touch panel module 6.

FIG. 2 is a block diagram showing an outline configuration of theelectronic device 1 according to the present embodiment. In theelectronic device 1 shown in this figure, the touch panel module 6includes a Touch panel unit 5 and a touch panel controller 8 forexchanging a transmission signal and a receiving signal with the Touchpanel unit 5. The device control unit 9 exchanges a coordinate signalwith the touch panel controller 8 and provides a display signal to theLiquid crystal display unit 4. The touch panel unit 7 includes theLiquid crystal display unit 4 and the touch panel module 6.

The Liquid crystal display unit 4 of the touch panel unit 7 has aquadrangular shape and is used for display for the purpose of operationof the electronic device 1 and for display of an image or the like. TheTouch panel unit 5 has approximately the same quadrangular shape as theLiquid crystal display unit 4 and is overlaid on the Liquid crystaldisplay unit 4. The shape of the Liquid crystal display unit 4 and theTouch panel unit 5 is set to be quadrangular. However, the shape may berectangular or square.

FIG. 3 is a sectional view of FIG. 1 taken along line A-A. This figureshows the cross section of a center portion of the touch panel unit 7.The Touch panel unit 5 of the touch panel unit 7 includes a receivingsensor panel (a first sensor panel) 5-1 and a transmission sensor panel(a second sensor panel) 5-2. A cover panel 20 fabricated from glassmaterial is arranged immediately above the receiving sensor panel 5-1and the Liquid crystal display unit 4 is arranged immediately under thetransmission sensor panel 5-2. Further, a Back light unit 21 is arrangedimmediately under the Liquid crystal display unit 4 and a Battery unit22 is arranged immediately under the Back light unit 21.

FIG. 4 is a perspective view showing arrangement relation between thecover panel 20, the Touch panel unit 5, the receiving sensor panel 5-1and the transmission sensor panel 5-2, and the Liquid crystal displayunit 4. As shown in the figure, the cover panel 20, the receiving sensorpanel 5-1, the transmission sensor panel 5-2, the Liquid crystal displayunit 4 are is arranged in this order.

FIG. 5 is a plan view diagram showing the receiving sensor panel 5-1 ofthe Touch panel unit 5. As shown in the figure, the receiving sensorpanel 5-1 is formed in a quadrangular shape and includes: a plurality ofreceiving electrodes 5-1 a arranged in a horizontal direction inparallel from the upper end toward the lower end; and two transmissionelectrodes 5-1 b arranged in a vertical direction respectively on theleft end side and the right end side. Each receiving electrode 5-1 a andeach transmission electrode 5-1 b are constructed from a plurality ofelectrode pieces P having a rhombus shape. The electrode piece P locatedat the tip of each of the two transmission electrodes 5-1 b has atriangular shape.

FIG. 6 is a plan view diagram showing the transmission sensor panel 5-2of the Touch panel unit 5. As shown in the figure, the transmissionsensor panel 5-2 is formed in a quadrangular shape similarly to thereceiving sensor panel 5-1 and includes: a plurality of transmissionelectrodes 5-2 c arranged in a vertical direction in parallel from theleft end toward the right end (the reverse direction may be employed).Similarly to each receiving electrode 5-1 a and each transmissionelectrode 5-1 b of the receiving sensor panel 5-1, each transmissionelectrode 5-2 c includes a plurality of electrode pieces P having arhombus shape. Here, the electrode piece P located at the tip of each ofthe transmission electrodes 5-2 c has a triangular shape.

FIG. 7 is a plan view diagram showing a state that the receiving sensorpanel 5-1 and the transmission sensor panel 5-2 are overlaid with eachother. As shown in the figure, when the receiving sensor panel 5-1 andthe transmission sensor panel 5-2 are overlaid with each other, thetransmission electrodes 5-1 b on the left end side and the right endside of the receiving sensor panel 5-1 and the transmission electrodes5-2 c on the left end side and the right end side of the transmissionsensor panel 5-2 overlap with each other, while the other electrodes donot overlap with each other and arranged alternately in vertical andhorizontal directions.

Here, in the electronic device 1 according to the present embodiment,90% or more of the area of the receiving sensor panel 5-1 overlaps withthe transmission sensor panel 5-2. Further, the region where thereceiving sensor panel 5-1 and the transmission sensor panel 5-2 overlapwith each other serves as the response region of the touch panel module6. The two transmission electrodes 5-1 b of the receiving sensor panel5-1 are arranged in the outermost periphery of the response region. Inthis case, when the shape of the Touch panel unit 5 is rectangular, thetwo transmission electrodes 5-1 b are arranged respectively along thetwo sides opposite to each other. The number of the transmissionelectrodes 5-1 b of the receiving sensor panel 5-1 may be one oralternatively three or more.

Returning to FIG. 2, the touch panel controller 8 applies a transmissionsignal on all the transmission electrodes 5-2 c of the transmissionsensor panel 5-2. In this application, order of application may bechanged arbitrarily under the control of the touch panel controller 8.Thus, all the transmission signals may be sent out in synchronization.The transmission signal is applied sequentially one by one from thetransmission electrode 5-2 c arranged at the left end to thetransmission electrode 5-2 c arranged at the right end. Further, whenapplying the transmission signal on the transmission electrode 5-2 carranged at the left end and the transmission electrode 5-2 c arrangedat the right end, at the same timing, the touch panel controller 8applies the transmission signal also on the transmission electrode 5-1 barranged on the left end side of the receiving sensor panel 5-1 and thetransmission electrode 5-1 b arranged on the right end side. That is, atthe same time that the transmission signal is applied on thetransmission electrode 5-2 c arranged at the left end, the sametransmission signal is applied also on the transmission electrode 5-1 barranged on the left end side. Further, at the same time that thetransmission signal is applied on the transmission electrode 5-2 carranged at the right end, the same transmission signal is applied alsoon the transmission electrode 5-1 b arranged at the right end.

Further, at the same time that the transmission signal is applied on thetransmission electrode 5-2 c of the transmission sensor panel 5-2, thetouch panel controller 8 detects the transmission signal in all thereceiving electrodes 5-1 a of the receiving sensor panel 5-1. That is,at the same time that the transmission signal is applied on one of thetransmission electrodes 5-2 c, the transmission signal is detectedsequentially from the receiving electrode 5-1 a arranged on the upperend side and to the receiving electrode 5-1 a arranged at the lower end.The transmission signal having been detected is referred to as areceiving signal, hereinafter.

FIG. 8 is a timing chart showing the operation of the touch panelcontroller 8. In this figure, “TxAC1” indicates a transmission signal tobe applied on the transmission electrode 5-1 b arranged on the left endside of the receiving sensor panel 5-1, “Tx1” indicates a transmissionsignal to be applied on the transmission electrode 5-2 c arranged on theleft end side of the transmission sensor panel 5-2, and “Rx1 to n”indicates a receiving signal obtained by all the receiving electrodes5-1 a of the receiving sensor panel 5-1. Further, “Tx2” indicates atransmission signal to be applied on the transmission electrode 5-2 carranged at the second position relative to the left end of thetransmission sensor panel 5-2, “Txn” indicates a transmission signal tobe applied on the transmission electrode 5-2 c arranged on the right endside of the transmission sensor panel 5-2, and “TxAC2” indicates atransmission signal to be applied on the transmission electrode 5-1 barranged on the right end side of the receiving sensor panel 5-1.

As shown in FIG. 8, at each time that the transmission signal is appliedsequentially one by one on all the transmission electrodes 5-2 c of thetransmission sensor panel 5-2, receiving is performed by all thereceiving electrodes 5-1 a of the receiving sensor panel 5-1. Here, whenthe transmission signal is applied on the transmission electrode 5-2 carranged on the left end side of the transmission sensor panel 5-2, thesame transmission signal is applied also on the transmission electrode5-1 b arranged on the left end side of the receiving sensor panel 5-1.Further, when the transmission signal is applied on the transmissionelectrode 5-2 c arranged on the right end side of the transmissionsensor panel 5-2, the same transmission signal is applied also on thetransmission electrode 5-1 b arranged on the right end side of thereceiving sensor panel 5-1. However, this case corresponds to operationperformed at not-yet-detected time that a person's hand is not detected,that is, at the time that a person's hand is located in anot-yet-detected area. When a person's hand is detected, that is, when aperson's hand enters an approaching detection area, the transmissionsignal is not applied on the two transmission electrodes 5-1 b arrangedon the left end side and the right end side of the receiving sensorpanel 5-1 and hence these electrodes go into a ground potential.

When the transmission signal is applied on both of the transmissionelectrode 5-2 c arranged on the left end side of the transmission sensorpanel 5-2 and the transmission electrode 5-1 b arranged on the left endside of the receiving sensor panel 5-1, a high sensitivity state inwhich the electric field becomes strong is established so thatapproaching of a person's hand can be detected with high sensitivity. Onthe contrary, when the transmission signal is no longer applied on thetransmission electrode 5-1 b arranged on the left end side of thereceiving sensor panel 5-1, the transmission electrode 5-1 b blocks theelectric field of the transmission electrode 5-2 c arranged on the leftend side of the transmission sensor panel 5-2 so that a low sensitivitystate is established. In the low sensitivity state, at the time that theelectronic device 1 is held with the hand, recognition as operation canbe avoided even when fingers touch the left and the right end parts ofthe Touch panel unit 5. This situation holds similarly in a case thatthe transmission signal is applied on both of the transmission electrode5-2 c arranged on the right end side of the transmission sensor panel5-2 and the transmission electrode 5-1 b arranged on the right end sideof the receiving sensor panel 5-1.

As such, the two transmission electrodes 5-1 b of the receiving sensorpanel 5-1 are provided in order that at the time that the electronicdevice 1 is held with the hand, the device control unit 9 should beprevented from recognizing as operation even when fingers approach theleft and the right end parts of the Touch panel unit 5. Here, it ispreferable that as shown in FIG. 9, the two transmission electrodes 5-1b are arranged between an edge of the Touch panel unit 5 and a pointthat internally divides the edge of the Touch panel unit 5 and thecenter of the Touch panel unit 5 into a ratio of 1 to 4 along a linepassing through the center (e.g., the center of gravity) of the Touchpanel unit 5. Further, also the number of the transmission electrodes5-1 b is not limited to one each in the left and the right and may beone or more.

In addition to the processing described above, the device control unit 9outputs a display signal for causing the Liquid crystal display unit 4to perform predetermined display at not-yet-detected time thatapproaching of a person's hand is not detected, and stops the output ofthe display signal when approaching of a person's hand is detected. Thiscauses the user of the electronic device 1 to recognize that thesensitivity of the peripheral edge part of the Touch panel unit 5 israised.

FIGS. 10( a) and 10(b) are diagrams showing a change in display of theLiquid crystal display unit 4 at not-yet-detected time that approachingof a person's hand is not detected and at the time that approaching of aperson's hand is detected. As shown in FIG. 10( a) of this figure, atnot-yet-detected time that approaching of a person's hand is notdetected, belted display 30 (e.g., display in orange color) is performedin the peripheral edge part of the Liquid crystal display unit 4. Whenapproaching of a person's hand is detected, as shown in FIG. 10( b) ofthis figure, the belted display 30 is no longer performed.

When a person's hand approaches the Touch panel unit 5, the receivingsignal varies in the receiving electrode 5-1 a of the receiving sensorpanel 5-1 located in the part of approaching. Thus, from the coordinatesignal corresponding to the receiving electrode 5-1 a in which thereceiving signal has varied, the device control unit 9 identifies thepart where the hand approaches.

The touch panel controller 8 and the device control unit 9 areconstructed from a CPU (Central Processing Unit), a ROM (Read OnlyMemory), a RAM (Random Access Memory), and an interface circuit. The ROMstores a program for controlling the CPU. The RAM is used in theoperation of the CPU.

Next, the operation of the electronic device 1 according to the presentembodiment is described below.

FIG. 11 is a flow chart used for describing the operation of the touchpanel controller 8 of the electronic device 1 according to the presentembodiment. The flow chart shown in this figure shows the operation of acase that a transmission signal is applied on each of the transmissionelectrode 5-1 b arranged on the left end side of the receiving sensorpanel 5-1 and the transmission electrode 5-2 c arranged on the left endside of the transmission sensor panel 5-2.

First, the touch panel controller 8 applies the transmission signalsTxAC1 and Tx1 at the same timing onto the transmission electrode 5-1 barranged on the left end side of the receiving sensor panel 5-1 and thetransmission electrode 5-2 c of the transmission sensor panel 5-2 (stepS1). After the application of the transmission signals TxAC1 and Tx1, onthe basis of receiving signals Rx1 to Rxn received by all the receivingelectrodes 5-1 a of the receiving sensor panel 5-1, transmission signalsTx1 to Txn and TxAC1 are detected (step S2). After the detection of thetransmission signals Tx1 to Txn and TxAC1, the receiving signals Rx1 toRxn undergo digital conversion so that a Z-value is calculated (stepS3). Then, it is judged whether the calculated Z-value is greater thanor equal to a TxAC1 switching threshold (step S4). Here, the TxAC1switching threshold indicates a value corresponding to the Z-value of acase that the electronic device 1 is grasped by a person.

When the calculated Z-value is less than the TxAC1 switching threshold(i.e., in case of “NO” in the judgment at step S4), the procedurereturns to step S1. In case of being greater than or equal to the TxAC1switching threshold (i.e., in case of “YES” in the judgment at step S4),the transmission electrode 5-1 b arranged on the left end side of thereceiving sensor panel 5-1 is set at a ground potential so that thetransmission signal TxAC1 is set to be zero level (step S5). After that,the present processing is terminated.

Here, in a case that the transmission signal is applied on each of thetransmission electrode 5-1 b arranged on the right end side of thereceiving sensor panel 5-1 and the transmission electrode 5-2 c arrangedon the right end side of the transmission sensor panel 5-2, it issufficient that the left end side is replaced by the right end side andthe transmission signal TxAC1 is replaced by TxAC2.

As such, according to the electronic device 1 according to the presentembodiment, the electronic device includes: the touch panel unit 7having the Liquid crystal display unit 4 and the Touch panel unit 5 ofcapacitive sensing type; the touch panel controller 8 for exchanging atransmission signal and a receiving signal with the Touch panel unit 5of the touch panel module 6; and the device control unit 9 forexchanging a coordinate signal with the touch panel controller 8 andproviding a display signal to the Liquid crystal display unit 4. Then,the Touch panel unit 5 includes: the receiving sensor panel 5-1including the plurality of receiving electrodes 5-1 a arranged in ahorizontal direction in parallel and the two transmission electrodes 5-1b arranged respectively on the left end side and the right end side in avertical direction; and the transmission sensor panel 5-2 including theplurality of transmission electrodes 5-2 c arranged in a verticaldirection in parallel from the left end toward the right end. Then, anidentical transmission signal is applied on both of the transmissionelectrode 5-2 c of the transmission sensor panel 5-2 and thetransmission electrode 5-1 b of the receiving sensor panel 5-1 so thatapproaching of a person's hand is detected with high sensitivity. Afterthe detection of approaching of a person's hand, the transmissionelectrode 5-1 b of the receiving sensor panel 5-1 is set at a groundpotential so that the sensitivity is reduced. Thus, the influence of thehand to the hand-held part at the time that the electronic device 1 isheld is suppressed.

Here, in the electronic device 1 according to the present embodiment,the receiving sensor panel 5-1 has been constructed from the pluralityof receiving electrodes 5-1 a and the two transmission electrodes 5-1 b.However, the two transmission electrodes 5-1 b may be constructed on apanel (a third sensor panel) other than the receiving sensor panel 5-1.Further, it is preferable that 90% or more of the area of the thirdsensor panel overlaps with the transmission sensor panel 5-2.

That is, in the electronic device 1 according to the present embodiment,the plurality of receiving electrodes 5-1 a and the two transmissionelectrodes 5-1 b are formed on the surface (the surface on the outerside in the electronic device 1) of the receiving sensor panel 5-1 (thefirst sensor panel), and the plurality of transmission electrodes 5-2 care formed on the surface (the surface on the outer side in theelectronic device 1) of the transmission sensor panel 5-2 (the secondsensor panel). However, the two transmission electrodes 5-1 b may beformed on the surface (the surface on the outer side in the electronicdevice 1) of a panel (the third sensor panel) other than the receivingsensor panel 5-1.

Further, it is sufficient that the plurality of receiving electrodes 5-1a, the two transmission electrodes 5-1 b, and the plurality oftransmission electrodes 5-2 c are arranged on any of the surface (thesurface on the outer side in the electronic device 1) or the rear face(the surface on the inner side in the electronic device 1) of one ormore sensor panels. For example, at least one of the transmissionelectrodes 5-1 b may be arranged on the surface (the first surface) ofthe receiving sensor panel 5-1 (the first sensor panel), the receivingelectrodes 5-1 a may be arranged on the rear face (the second surface)of the receiving sensor panel 5-1, and the transmission electrodes 5-2 cmay be arranged on the rear face (the third surface) of the transmissionsensor panel 5-2 (the second sensor panel).

Further, in the electronic device 1 according to the present embodiment,as shown in the timing chart of FIG. 8, the transmission signal areapplied sequentially one by one on the plurality of transmissionelectrodes 5-2 c of the transmission sensor panel 5-2. However, as shownin the timing chart of FIG. 12, the transmission signal may be appliedat the same timing to all of the plurality of transmission electrodes5-2 c of the transmission sensor panel 5-2.

Further, in the electronic device 1 according to the present embodiment,the program describing the processing shown in the flow chart of FIG. 11has been stored in the ROM. However, the program may be stored in astorage medium such as a magnetic disc, an optical disc, amagneto-optical disc, and a flash memory and then distributed.Alternatively, the program may be saved in a server (not shown) on anetwork such as the Internet and then downloaded through atelecommunication line.

Embodiment 2

FIG. 13 is a front view showing an outline of an electronic deviceaccording to Embodiment 2 of the present invention. In this figure, theelectronic device 40 according to the present embodiment is a portablewireless device referred to as a smart phone similar to the electronicdevice 1 according to Embodiment 1 described above. Then, a receiver 42is provided in an upper part on the front face side of a housing 41formed in a quadrangular shape, and a touch panel module 43 ofcapacitive sensing type is provided under the receiver 42. Further,three function buttons 44-1 to 44-3 are provided under the touch panelmodule 43.

FIG. 14 is a block diagram showing an outline configuration of theelectronic device 40 according to the present embodiment. In thisfigure, the electronic device 40 according to the present embodimentincludes the touch panel module 43 described above, a Display unit 45,and a device control unit 46. The touch panel module 43 includes a Touchpanel unit 47 and a touch panel controller 48 for exchanging atransmission signal and a receiving signal with the Touch panel unit 47.The device control unit 46 exchanges a coordinate signal with the touchpanel module 43 and provides a display signal to the Display unit 45.The Display unit 45 and the touch panel module 43 constitute a touchpanel unit 49. The device control unit 46 and the touch panel controller48 are constructed from a CPU, a ROM, a RAM, and an interface circuit.The ROM stores a program for controlling the CPU. The RAM is used in theoperation of the CPU.

The Display unit 45 has a quadrangular shape and is used for display forthe purpose of operation of the electronic device 40 and for display ofan image or the like. In the Display unit 45, an LCD (Liquid CrystalDisplay), an organic EL (Electro Luminescence), or an electronic paperis employed. The Touch panel unit 47 has a quadrangular shapeapproximately the same as the Display unit 45 and is overlaid on theDisplay unit 45. Here, the Display unit 45 and the Touch panel unit 47may be arranged in the inside of the housing 41 or alternatively in theoutside. However, in whichever case, the Touch panel unit 47 is arrangedon the outer side relative to the Display unit 45. Further, in theelectronic device 40 according to the present embodiment, the shape ofthe Display unit 45 and the Touch panel unit 47 is set to bequadrangular. However, the shape may be rectangular or square.

The electronic device 40 according to the present embodiment is capableof character input. For example, when an application for generating anE-mail is started, a mail screen as shown in FIG. 13 is displayed andthen character input is allowed in this mail screen. The mail screenshown in FIG. 13 contains a destination input display region 50, asubject input display region 51, an input display region 52, and acharacter kind selection key display region 53. These display regions 50to 53 are set up in the Touch panel unit 47. The display position of theinput display region 52 may be fixed or alternatively may be variable.The character kind selection key display region 53 includes a kanacharacter input key display region 531, a numeric character input keydisplay region 532, an alphabetical character input key display region533, a symbol input key display region 534, and a pictorial symbol inputkey display region 535. The display positions of the individual displayregions 531 to 535 may be fixed or alternatively may be variable. In theTouch panel unit 47, a character kind selection key 54 is set up incorrespondence to the character kind selection key display region 53.Here, the kana character input key display region 531, the numericcharacter input key display region 532, the alphabetical character inputkey display region 533, the symbol input key display region 534, and thepictorial symbol input key display region 535 individually correspond toa predetermined display region and a first display region.

The character kind selection key 54 includes a kana character input key541, a numeric character input key 542, an alphabetical character inputkey 543, a symbol input key 544, and a pictorial symbol input key 545.When each key is operated, a kana character, a numeric character, analphabetical character, a symbol, and a pictorial symbol can beinputted. In this case, characters inputted as a subject name aredisplayed in the subject input display region 51 of the Display unit 45and characters inputted for generating a text are displayed in the inputdisplay region 52 of the Display unit 45. The character kind selectionkey 54 serves as ten keys and hence a larger area is ensured for theinput display region 52 in comparison with an electronic device providedwith ten keys. Here, FIG. 44 is a diagram showing an example of a mailscreen in an electronic device 120 provided with ten keys. In the mailscreen shown in this figure, a destination input display region 130, asubject input display region 131, an input display region 132, a ten-keyinput display region 133, a character kind selection key display region134, a pictorial symbol/symbol/face mark selection key display region135, and the like are set up. Then, for these display regions, characterinput is performed by using ten keys 140, a character kind selection key141, and a pictorial symbol/symbol/face mark selection key 142. The areaof the input display region 132 is reduced by an amount corresponding tothe ten keys 140.

In FIG. 13, in the electronic device 40 according to the presentembodiment, in each of the kana character input key display region 531,the numeric character input key display region 532, the alphabeticalcharacter input key display region 533, the symbol input key displayregion 534, and the pictorial symbol input key display region 535 of thecharacter kind selection key display region 53, when an instructing bodysuch as a user's finger and a pen tip is brought close or apart, displaycan be performed in a manner of switching at least three kinds ofcharacters (including a kana character, a numeric character, analphabetical character, a symbol, and a pictorial symbol) inpredetermined order. The three kinds of characters and the predeterminedorder are successive three kinds and their order selected from at leastalphabets consisting of “A”, “B”, “C”, “D”, “E”, “F”, “G”, “H”, “I”,“J”, “K”, “L”, “M”, “N”, “O”, “P”, “Q”, “R”, “S”, “T”, “U”, “V”, “W”,“X”, “Y”, “Z”, “A”, “B”. Alternatively, they are successive three kindsand their order selected from at least numeric characters consisting of“1”, “2”, “3”, “4”, “5”, “6”, “7”, “8”, “9”, “0”, “1”, “2” oralternatively “0”, “1”, “2”, “3”, “4”, “5”, “6”, “7”, “8”, “9”, “10”,“11”. Alternatively, they are successive three kinds and their orderselected from at least Japanese characters consisting of “a”, “ka”,“sa”, “ta”, “na”, “ha”, “ma”, “ya”, “ra”, “wa”, “n”, “a”, “ka” oralternatively “i”, “ki”, “shi”, “chi”, “ni”, “hi”, “mi”, “i”, “ri”,“wi”, “i”, “ki”.

When display is performed in a manner of switching at least three kindsof characters in predetermined order, the user can select a desiredcharacter. After selecting a desired character, when the user goes intocontact with (i.e., touches) this character, the character is confirmed.Selection and confirmation of a character is described below withreference to an example.

(A Case of Alphabetical Character Input)

FIGS. 15 and 16( a) to 16(c) are diagrams schematically showingalphabetical character input operation. As shown in FIGS. 15 and 16( a),when a fingertip 60 is brought close to the alphabetical character inputkey display region (the first display region) 533 of the character kindselection key display region 53 to an extent of not going into contact(e.g., 1-mm immediately above the alphabetical character input keydisplay region 533), each character of the string “‘A’, ‘a’, A, a”(translator's note: single quotes (′) are used for explicitly indicatinga full-size character) is displayed in each of the display regions (thesecond display regions) 550 to 553 on the left side in a horizontaldirection from the alphabetical character input key display region 533.Further, each character of the string “B′, ‘b’, B, b” is displayed ineach of the display regions (the second display regions) 554 to 557 inan oblique upper left direction, each character of the string “C′, ‘c’,C, c” is displayed in each of the display regions (the second displayregions) 558 to 561 in an upward direction, each character of the string“D′, ‘d’, D, d” is displayed in each of the display regions (the seconddisplay regions) 562 to 565 in an oblique upper right direction, andeach character of the string “E′, ‘e’, E, e” is displayed in each of thedisplay regions (the second display regions) 566 to 569 on the rightside in a horizontal direction. Here, each character string includes a“full-size upper-case character”, a “full-size lower-case character”, a“half-width upper-case character”, and a “half-width lower-casecharacter”. Here, in FIGS. 15 and 16( a) to 16(c), the alphabeticalcharacter input key display region 533 serving as the first displayregion and the second display regions 550 to 569 are close to eachother. However, they may be apart from each other.

In a state that alphabetical character candidates with beginningcharacters “‘A’, ‘B’, ‘C’, ‘D’, ‘E’” are displayed, when the fingertip60 is brought apart upward, the displayed alphabetical charactercandidates vary successively and, finally, alphabetical charactercandidates with beginning characters “‘V’, ‘W’, ‘X’, ‘Y’, ‘Z’” aredisplayed. In this position, each character of the string “‘V’, ‘v’, V,v” is displayed in each of the display regions 550 to 553 on the leftside in a horizontal direction from the alphabetical character input keydisplay region 533. Further, each character of the string “‘W’, ‘w’, W,w” is displayed in each of the display regions 554 to 557 in an obliqueupper left direction, each character of the string “‘X’, ‘x’, X, x” isdisplayed in each of the display regions 558 to 561 on in an upwarddirection, each character of the string “‘Y’, ‘y’, Y, y” is displayed ineach of the display regions 562 to 565 in an oblique upper rightdirection, and each character of the string “‘Z’, ‘z’, Z, z” isdisplayed in each of the display regions 566 to 569 on the right side ina horizontal direction.

In a state that alphabetical character candidates with beginningcharacters “‘V’, ‘W’, ‘X’, ‘Y’, ‘Z’” are displayed, when the fingertip60 is moved in the opposite direction, that is, brought close to thealphabetical character input key display region 533, the displayedalphabetical character candidates vary successively in the oppositedirection. That is, the display varies in reverse order to the previousone. As such, when the fingertip 60 is brought apart or close relativeto the alphabetical character input key display region 533, thedisplayed alphabetical character candidates vary successively and hencea desired alphabetical character candidate can be selected.

Here, the distance between the fingertip 60 and the alphabeticalcharacter input key display region 533 is the distance to the Touchpanel unit 47. However, the distance to the Display unit 45 may beemployed. Alternatively, the distance to the housing 41 may be employed.

Further, the order of the alphabetical character candidates varyingsuccessively in response to the operation of the fingertip 60 is notchanged.

Further, after the fingertip 60 is brought apart until alphabeticalcharacter candidates with beginning characters “‘V’, ‘W’, ‘X’, ‘Y’, ‘Z’”are displayed, when the fingertip 60 is brought apart further,circulation may be performed such that alphabetical character candidates“‘A’, ‘B’, ‘C’, ‘D’, ‘E’” are displayed again. However, the distanceneed be such that the fingertip 60 can be detected.

After a desired alphabetical character candidate is selected, when thedisplay region (the second display region) of the selected alphabeticalcharacter candidate is brought into contact (i.e., touched), theselected alphabetical character candidate is confirmed. For example,when “‘E’” of full-size upper-case character is to be confirmed, asshown in FIG. 16( b), the fingertip 60 is moved horizontally to thedisplay region (the second display region) where “‘E’” is displayed.After that, as shown in FIG. 16( c), the fingertip 60 is brought intocontact with (i.e., caused to touch) the display region 566 where “‘E’”is displayed. As a result, “‘E’” of full-size upper-case character isconfirmed. When the fingertip 60 exits the alphabetical character inputkey display region 533 and then enters the display region 566 where theselected alphabetical character candidate is displayed, the selectedalphabetical character candidate is displayed continuously. That is,even when the distance from the display region to the fingertip 60 ischanged (i.e., even when the fingertip is changed up and down), thealphabetical character candidate is not switched.

Here, when the selected alphabetical character candidate is to beconfirmed, the fingertip 60 need not go into contact with the entiretyof the display region (the second display region). That is, contact to acertain extent is sufficient.

Further, the display regions (the second display regions) for displayingalphabetical characters in the surroundings of the fingertip 60 havebeen provided in the number of five characters (e.g., ‘A’, ‘B’, ‘C’,‘D’, ‘E’) (20 pieces). Instead, the regions may be provided in thenumber of more than five characters.

(A Case of Kana Character Input)

FIGS. 17 and 18( a) to 18(c) are diagrams schematically showing kanacharacter input operation. As shown in FIGS. 17 and 18( a), when thefingertip 60 is brought close to the kana character input key displayregion (the predetermined display region and the first display region)531 of the character kind selection key display region 53 (in thisexample, the kana character input key display region 531 is premised tobe located in the center of the character kind selection key displayregion 53) to an extent of not going into contact (e.g., 1-mmimmediately above the kana character input key display region 531), “a”(translators note: double quotes (”) are used for indicating Japanesekana characters when kana characters are mentioned) is displayed in thedisplay region 550 adjacent on the left of the kana character input keydisplay region 531. Further, “i” is displayed in the display region 554on the oblique upper left side, “u” is displayed in the display region558 on the upper side, “e” is displayed in the display region 562 on theoblique upper right side, and “o” is displayed in the display region 566adjacent on the right.

In a state that kana character candidates “a, i, u, e, o” are displayed,when the fingertip 60 is brought apart upward (e.g., brought apartupward by 1 mm), kana character candidates “ka, ki, ku, ke, ko” aredisplayed. From this position, when the fingertip 60 is further broughtapart upward (e.g., brought apart upward by 1 mm), kana charactercandidates “sa, shi, su, se, so” are displayed. After that, when thefingertip 60 is continued to be brought apart upward, the displayed kanacharacter candidates vary successively. Then, after kana charactercandidates “wa, wi, u, we, wo” are displayed, at last, kana charactercandidates “n, a, i, u, e” are displayed (“a, i, u, e” except for “n”are re-used).

In a state that kana character candidates “n, a, i, u, e, o” aredisplayed, when the fingertip 60 is moved in the opposite direction,that is, the fingertip 60 is brought close to the kana character inputkey display region (the predetermined display region and the firstdisplay region) 531, the displayed kana character candidates varysuccessively in the opposite direction. That is, the display varies inreverse order to the previous one. As such, when the fingertip 60 isbrought apart or close relative to the kana character input key displayregion (the predetermined display region and the first display region)531, the displayed kana character candidates vary successively and hencea desired kana character candidate can be selected.

Here, the distance between the fingertip 60 and the kana character inputkey display region 531 is the distance to the Touch panel unit 47.However, the distance to the Display unit 45 may be employed.Alternatively, the distance to the housing 41 may be employed.

Further, the order of the kana character candidates varying successivelyin response to the operation of the fingertip 60 is not changed.

Further, after the fingertip 60 is brought apart until kana charactercandidates “n, a, i, u, e” are displayed, when the fingertip 60 isbrought apart further, circulation may be performed such that kanacharacter candidates “a, i, u, e, o” are displayed again. However, thedistance need be such that the fingertip 60 can be detected.

After a desired kana character candidate is selected, when the displayregion (the second display region) of the selected kana charactercandidate is brought into contact (i.e., touched), the selected kanacharacter candidate is confirmed. For example, when “o” is to beconfirmed, as shown in FIG. 18( b), the fingertip 60 is movedhorizontally to the display region 566 where “o” is displayed. Afterthat, as shown in FIG. 18( c), the fingertip 60 is brought into contactwith (i.e., caused to touch) the display region 566 where “o” isdisplayed. As a result, “o” is confirmed. When the fingertip 60 exitsthe kana character input key display region 531 and then enters thedisplay region (the second display region) where the selected kanacharacter candidate is displayed, the selected kana character candidateis displayed continuously. That is, even when the distance from thedisplay region to the fingertip 60 is changed (i.e., even when thefingertip is changed up and down), the kana character candidate is notswitched.

Here, when the selected kana character candidate is to be confirmed, thefingertip 60 need not go into contact with the entirety of the displayregion (the second display region). That is, contact to a certain extentis sufficient.

Further, the display regions (the second display regions) for displayingkana characters in the surroundings of the fingertip 60 have beenprovided in the number of five characters (e.g., “a”, “i”, “u”, “e”,“o”) (five pieces). Instead, the regions may be provided in the numberof more than five characters.

Further, in addition to the above-mentioned hiragana (hira-kana)notation, kata-kana notation and Roman character notation may beemployed.

Further, display, selection, and confirmation can be performed similarlyfor Roman numerals and Chinese numerals.

Further, even for any language other than English, display, selection,and confirmation can be performed in the language.

Next, finger detection in the electronic device 40 according to thepresent embodiment is described below.

FIG. 19 is a diagram showing the positional relation between thefingertip 60 and the Touch panel unit 47 at the time of character input.As shown in the figure, when the distance Za from the fingertip 60 tothe Touch panel unit 47 falls between Z0 and Z1, the fingertip 60 isdetected. In this case, with taking into consideration the blur of thefingertip 60, the distance is calculated as the average within apredetermined time. FIG. 20 is a diagram showing a time-dependent changein the distance between the fingertip 60 and the Touch panel unit 47 atthe time of character input. As shown in the figure, between Z0 and Z1,the average of the distance is calculated between time t1 and time t2.When the average of the distance falls between Z0 and Z1, the fingertip60 is detected.

Next, character input processing of the electronic device 40 accordingto the present embodiment is described below.

FIG. 21 is a flow chart showing the character input processing of theelectronic device 40 according to the present embodiment. Here, thepresent processing is performed mainly by the device control unit 46 andthe touch panel controller 48. In this figure, the touch panelcontroller 48 judges whether the Touch panel unit 47 has detected afinger (step S11). When a finger is not detected (i.e., when “No” isconcluded in the judgment at step S11), the present judgment is repeateduntil a finger is detected. In contrast, when a finger has been detected(i.e., when “Yes” is concluded in the judgment at step S11), thecoordinates (X,Y,Z) of the detected finger are calculated (step S12).Then, the calculated coordinates (X,Y,Z) are outputted as the coordinatesignal to the device control unit 46.

The device control unit 46 compares the signal value of the Z-coordinateof the coordinate signal outputted from the touch panel controller 48.Here, comparison with four ranges of signal value is premised to beperformed. A first range of signal value is “Za0<Z<Za1”, a second rangeof signal value is “Zb0<Z<Zb1”, a third range of signal value is“Zc0<Z<Zc1”, and a fourth range of signal value is “Zd0<Z<Zd1”. Further,the magnitude relations between these ranges are such that the firstrange of signal value<the second range of signal value<the third rangeof signal value<the fourth range of signal value. In the case of kanacharacter input, the first range of signal value is a range in which “a,i, u, e, o” are to be selected. Further, the second range of signalvalue is a range in which “ka, ki, ku, ke, ko” are to be selected, thethird range of signal value is a range in which “sa, shi, su, se, so”are to be selected, and the fourth range of signal value is a range inwhich “ta, chi, tsu, te, to” are to be selected. Since, the kanacharacters consist of 50 characters, for the remaining characters, up toa tenth range of signal value for the “wa” row becomes necessary.However, there is “n” in addition. When “i, u, e, o” is re-used, aneleventh range of signal value need be added.

When the device control unit 46 judges that the signal value of theZ-coordinate of the coordinate signal outputted from the touch panelcontroller 48 falls within the first signal value range “Za0<Z<Za1”(i.e., when “Yes” is concluded in the judgment at step S13), among thecandidate characters (“a, i, u, e, o”) of the character string for Za,“a” is displayed in the display region 550 adjacent on the left of thekana character input key display region 531 of the character kindselection key display region 53. Further, “i” is displayed in thedisplay region 554 on the oblique upper left side, “u” is displayed inthe display region 558 on the upper side, “e” is displayed in thedisplay region 562 on the oblique upper right side, and “o” is displayedin the display region 566 adjacent on the right (step S17).

On the other hand, when judging that the signal value of theZ-coordinate of the coordinate signal outputted from the touch panelcontroller 48 falls within the second signal value range “Zb0<Z<Zb1”(i.e., when “Yes” is concluded in the judgment at step S14), the devicecontrol unit 46 displays the candidate characters (“ka, ki, ku, ke, ko”)of the character string for Zb into each of the display regions 550,554, 558, 562, 566 around the kana character input key display region531 (step S21).

Further, when judging that the signal value of the Z-coordinate of thecoordinate signal outputted from the touch panel controller 48 fallswithin the third signal value range “Zc0<Z<Zc1” (i.e., when “Yes” isconcluded in the judgment at step S15), the device control unit 46displays the candidate characters (“sa, shi, su, se, so”) of thecharacter string for Zc into each of the display regions 550, 554, 558,562, 566 around the kana character input key display region 531 (stepS25).

Further, when judging that the signal value of the Z-coordinate of thecoordinate signal outputted from the touch panel controller 48 fallswithin the fourth signal value range “Zd0<Z<Zd1” (i.e., when “Yes” isconcluded in the judgment at step S16), the device control unit 46displays the candidate characters (“ta, chi, tsu, te, to”) of thecharacter string for Zd into each of the display regions 550, 554, 558,562, 566 around the kana character input key display region 531 (stepS29).

After the device control unit 46 displays the candidate characters ofthe character string for Za, the touch panel controller 48 re-calculatesthe coordinates (X,Y) of the finger (step S18). This processing isperformed for judging which character candidate has been selected amongthe candidate characters of the character string for Za. After there-calculation of the coordinates (X,Y) of the finger, it is judgedwhether the absolute value |(X,Y)−(Xa,Ya)| of the deviation from thecandidate character coordinates is smaller than a detection thresholdset up in advance, that is, whether the absolute value of the deviationfrom the candidate character coordinates |(X,Y)−(Xa,Ya)|<the detectionthreshold (step S19). In this judgment, when the absolute value|(X,Y)−(Xa,Ya)| of the deviation from the candidate charactercoordinates is smaller than the detection threshold, the candidatecoordinates (Xa,Ya) are selected (step S20). For example, as shown inFIG. 18( b), when the fingertip 60 is premised to be located at aposition corresponding to the position for the character “o” or itsadjacent position, this position is selected as the candidatecoordinates (Xa,Ya). At that time, (X,Y) are the coordinates of thesecond display region 566. When the absolute value |(X,Y)−(Xa,Ya)| ofthe deviation from the candidate character coordinates is greater thanor equal to the detection threshold, the procedure goes to step S23.

On the other hand, when the touch panel controller 48 has re-calculatedthe coordinates (X,Y) of the finger (step S22), the device control unit46 judges whether the absolute value |(X,Y)−(Xb,Yb)| of the deviationfrom the candidate character coordinates is smaller than the detectionthreshold, that is, whether the absolute value of the deviation from thecandidate character coordinates |(X,Y)−(Xb,Yb)|<the detection threshold(step S23). In this judgment, when the absolute value |(X,Y)−(Xb,Yb)| ofthe deviation from the candidate character coordinates is smaller thanthe detection threshold, the candidate coordinates (Xb,Yb) are selected(step S24). When the absolute value |(X,Y)−(Xb,Yb)| of the deviationfrom the candidate character coordinates is greater than or equal to thedetection threshold, the procedure goes to step S27.

Further, when the touch panel controller 48 has re-calculated thecoordinates (X,Y) of the finger (step S26), the device control unit 46judges whether the absolute value |(X,Y)−(Xc,Yc)| of the deviation fromthe candidate character coordinates is smaller than the detectionthreshold, that is, whether the absolute value of the deviation from thecandidate character coordinates |(X,Y)−(Xc,Yc)|<the detection threshold(step S27). In this judgment, when the absolute value |(X,Y)−(Xc,Yc)| ofthe deviation from the candidate character coordinates is smaller thanthe detection threshold, the candidate coordinates (Xc,Yc) are selected(step S28). When the absolute value |(X,Y)−(Xc,Yc)| of the deviationfrom the candidate character coordinates is greater than or equal to thedetection threshold, the procedure goes to step S31.

Further, when the touch panel controller 48 has re-calculated thecoordinates (X,Y) of the finger (step S30), the device control unit 46judges whether the absolute value |(X,Y)−(Xd,Yd)| of the deviation fromthe candidate character coordinates is smaller than the detectionthreshold, that is, whether the absolute value of the deviation from thecandidate character coordinates |(X,Y)−(Xd,Yd)|<the detection threshold(step S31). In this judgment, when the absolute value |(X,Y)−(Xd,Yd)| ofthe deviation from the candidate character coordinates is smaller thanthe detection threshold, the candidate coordinates (Xd,Yd) are selected(step S32). When the absolute value |(X,Y)−(Xd,Yd)| of the deviationfrom the candidate character coordinates is greater than or equal to thedetection threshold, the procedure returns to step S11.

After selecting any one of the candidate coordinates (Xa,Ya), thecandidate coordinates (Xb,Yb), the candidate coordinates (Xc,Yc), andthe candidate coordinates (Xd,Yd), the device control unit 46 judgeswhether the selected candidate coordinates have been touched (step S33).When the candidate coordinates are not touched, the procedure returns tostep S11. When the candidate coordinates have been touched, thecharacter of the candidate coordinates is confirmed (step S34). Afterthe confirmation of the character, the present processing is terminated.

As such, according to the electronic device 40 according to the presentembodiment, when the fingertip 60 is not in contact with the Touch panelunit 47, the distance between the fingertip 60 and a predetermineddisplay region (the first display region; e.g., the alphabeticalcharacter input key display region 533) of the character kind selectionkey display region 53 is detected. Then, in response to an increase inthe distance between the fingertip 60 and the predetermined displayregion of the character kind selection key display region 53, pluralkinds of character candidates are displayed in a manner of beingswitched in predetermined order. Further, in response to a decrease inthe distance between the fingertip 60 and the predetermined displayregion of the character kind selection key display region 53, pluralkinds of character candidates are displayed in a manner of beingswitched in reverse order to the predetermined order adopted in the caseof increasing distance. Then, after the characters are switched anddisplayed, when the coordinates of the fingertip 60 exit thepredetermined display region of the character kind selection key displayregion 53, the operation is performed that the character switched anddisplayed is selected. Thus, a desired character can be selected by easyoperation like the fingertip 60 is brought close to or apart from thepredetermined display region of the character kind selection key displayregion 53 of the Touch panel unit 47 or alternatively brought outsidethe predetermined region so as to be moved to the second display region.Thus, operability improvement in character selection is achieved.

Here, the electronic device 40 according to the present embodiment hasbeen a portable wireless device referred to as a smart phone, however,is not limited to an electronic device of this kind. For example, anelectronic device of floor-standing type such as an ATM (AutomatedTeller Machine) may be employed.

Further, in the electronic device 40 according to the presentembodiment, the program describing the processing shown in the flowchart of FIG. 21 has been stored in the ROM. However, the program may bestored in a storage medium such as a magnetic disc, an optical disc, amagneto-optical disc, and a flash memory and then distributed.Alternatively, the program may be saved in a server (not shown) on anetwork such as the Internet and then downloaded through atelecommunication line.

Embodiment 3

FIG. 22 is a block diagram showing an outline configuration of anelectronic device according to Embodiment 3 of the present invention.Here, the electronic device 70 according to the present embodiment is aportable wireless device referred to as a smart phone similar to theelectronic device 1 according to Embodiment 1 and the electronic device40 according to Embodiment 2 described above. Thus, the outline issimilar to these and hence an outline diagram is omitted. Then, FIG. 1is referred to when necessary in description.

In FIG. 22, the electronic device 70 according to the present embodimentincludes a touch panel module 73, a Display unit 75, a device controlunit 76, a vibration feedback element 90, and a speaker 91. The touchpanel module 73 includes a Touch panel unit 77 and a touch panelcontroller 78 for exchanging a transmission signal and a receivingsignal with the Touch panel unit 77. The Display unit 75 includes anLCD, an organic EL, or an electronic paper and thereby performs displayfor the purpose of operation of the electronic device 70 and display ofan image or the like. The device control unit 76 performs processing(i.e., exchange of a coordinate signal with the touch panel controller78 and provision of a display signal to the Display unit 75) similar tothat of the device control unit 9 of the electronic device 1 accordingto Embodiment 1 described above. Further, in addition to this basicprocessing, the device control unit 76 performs also the processing ofperforming display, vibration, and sound emission for causing the userto recognize that the user has operated the electronic device 70. Asmeans for realizing this new processing, the device control unit 76includes a Grasping judgment unit 80, a Feedback switching unit 81, anda visual/auditory feedback unit 82.

Here, the Touch panel unit 77 corresponds to a sensor. Further, thevibration feedback element 90 corresponds to a vibration unit. Further,the Display unit 75 and the visual/auditory feedback unit 82 constitutea display device. Further, the speaker 91 and the visual/auditoryfeedback unit 82 constitute a sound emission unit. Further, the devicecontrol unit 76 and the touch panel controller 78 are constructed from aCPU, a ROM, a RAM, and an interface circuit. The ROM stores a programfor controlling the CPU. The RAM is used in the operation of the CPU.

On the basis of the coordinate signal obtained by the approachingdetection by the touch panel module 73, the Grasping judgment unit 80judges whether the electronic device 70 is grasped by the user. In thiscase, when the user grasps the electronic device 70, a coordinate signalof the peripheral edge part of the Touch panel unit 77 is outputted fromthe touch panel controller 78. When receiving this coordinate signal,the Grasping judgment unit 80 judges that the electronic device 70 isgrasped by the user. In a case that the electronic device 70 is judgedas being grasped by the user, when contact is detected in the Touchpanel unit 77, the Grasping judgment unit 80 outputs a switching signalfor using the vibration feedback element 90, to the Feedback switchingunit 81. Further, in a case that the electronic device 70 is judged asnot being grasped by the user, when contact is detected in the Touchpanel unit 77, the Grasping judgment unit 80 outputs a switching signalfor using the Display unit 75 and the speaker 91, to the Feedbackswitching unit 81. Here, the contact in the Touch panel unit 77indicates contact performed when an icon or the like on the touch panelis selected.

As such, when the electronic device 70 is grasped by the user, theGrasping judgment unit 80 selects the vibration feedback element 90.Then, in this state, when an icon or the like on the touch panel isselected, the Grasping judgment unit 80 starts the vibration feedbackelement 90. Further, when the electronic device 70 is not grasped by theuser, the Grasping judgment unit 80 selects the Display unit 75 and thespeaker 91. Then, in this state, when an icon or the like on the touchpanel is selected, the Grasping judgment unit 80 causes the Display unit75 to perform predetermined display and causes the speaker 91 to emitpredetermined sound.

When a switching signal for using the vibration feedback element 90 isinputted, the Feedback switching unit 81 continues, for a predeterminedtime, outputting a control signal for causing the vibration feedbackelement 90 to operate. Further, when a switching signal for using theDisplay unit 75 and the speaker 91 is inputted, the Feedback switchingunit 81 outputs the switching signal to the visual/auditory feedbackunit 82. For example, the vibration feedback element 90 is composed of avibrator, a piezo actuator, or a vibration actuator and vibrates duringthe time that the control signal is outputted from the Feedbackswitching unit 81. When the switching signal outputted from the Feedbackswitching unit 81 is inputted, the visual/auditory feedback unit 82continues, for a predetermined time, outputting a display signal forcausing the Display unit 75 to perform predetermined display andcontinues, for a predetermined time, outputting an audio signal forcausing the speaker 91 to output predetermined sound.

As such, when the user grasps the electronic device 70 and the Touchpanel unit 77 is brought into contact, the vibration feedback element 90vibrates. This vibration allows the user to recognize that operation hasbeen performed. FIG. 23 is a diagram showing a situation that theelectronic device 70 is held with the hand and operated by the user. Asshown in the figure, when the icon 701 is touched, vibration isgenerated.

On the other hand, in a state that the electronic device 70 is placed ona desk or the like, when the Touch panel unit 77 is brought intocontact, the vibration feedback element 90 does not vibrate. Instead,predetermined display is performed by the Display unit 75 andpredetermined sound is emitted from the speaker 91. The predetermineddisplay and the predetermined sound emission allows the user torecognize that the operation is performed in a state that the electronicdevice 70 is placed on a desk or the like. FIG. 24 is a diagram showinga situation that the electronic device 70 is placed and operated on adesk 110. As shown in the figure, When the icon 701 is touched,predetermined display 702 is displayed in the Display unit 75 andpredetermined sound (peep, peep, . . . ) is emitted from the speaker 91.

FIG. 25 is a sectional view showing an example of arrangement of thevibration feedback element 90 in the electronic device 70 according tothe present embodiment. Here, the sectional view shown in this figureshows the cross section of a center portion of the touch panel unit 79similarly to the sectional view of the touch panel unit 7 of theelectronic device 1 of Embodiment 1 shown in FIG. 3. The Touch panelunit 77 of the touch panel unit 79 includes a receiving sensor panel77-1 and a transmission sensor panel 77-2. A cover panel 20 fabricatedfrom glass material is arranged immediately above the receiving sensorpanel 77-1 and the Display unit 75 is arranged immediately under thetransmission sensor panel 77-2. Further, a Back light unit 21 isarranged immediately under the Display unit 75 and a Battery unit 22 isarranged immediately under the Back light unit 21. A vibrator 90 a (or avibration actuator 90 b) serving as the vibration feedback element 90 isarranged adjacent to the Battery unit 22 and a piezo actuator 90 c isarranged immediately under the peripheral edge part of the cover panel20. These members are accommodated in a housing 71. Here, thearrangement of the vibrator 90 a (the vibration actuator 90 b) and thepiezo actuator 90 c given above is merely exemplary. Further, all of thevibrator 90 a, the vibration actuator 90 b, and the piezo actuator 90 cmay be arranged. Alternatively, any one of these may be arranged.

FIG. 26 is a flow chart showing the operation notification processing ofthe electronic device 70 according to the present embodiment. In thisfigure, the Grasping judgment unit 80 performs grasping judgment on thebasis of approaching detection by the touch panel module 73 (step S41)and then judges whether the electronic device 70 is grasped by the user(step S42). In this judgment, when the electronic device 70 is judged asbeing grasped by the user (i.e., when “YES” is concluded in the judgmentat step S42), the vibration feedback element 90 is selected (step S43).Then, when an icon or the like on the touch panel is selected, theGrasping judgment unit 80 outputs to the Feedback switching unit 81 aswitching signal for using the vibration feedback element 90 and therebystarts the vibration feedback element 90 (step S44).

On the other hand, in the judgment at step S42, when the electronicdevice 70 is judged as not being grasped by the user (i.e., when “NO” isconcluded in the judgment at step S42), the Grasping judgment unit 80selects the Display unit 75 and the speaker 91 (step S45). Then, when anicon or the like on the touch panel is selected, the Grasping judgmentunit 80 outputs to the Feedback switching unit 81 a switching signal forusing the Display unit 75 and the speaker 91 and thereby causes theDisplay unit 75 to perform the predetermined display and causes thespeaker 91 to emit the predetermined sound (step S46).

As such, according to the electronic device 70 according to the presentembodiment, when the user grasps the electronic device 70 and goes intocontact with the Touch panel unit 77, the vibration feedback element 90is caused to vibrate. Further, in a state that the electronic device 70is placed on a desk or the like, when the Touch panel unit 77 is broughtinto contact, the vibration feedback element 90 is not caused tovibrate, instead, the Display unit 75 is caused to perform thepredetermined display and the speaker 91 is caused to emit thepredetermined sound. Thus, the user can recognize operation performed ina state that the electronic device 70 is held with the hand as well asoperation performed in a state of being placed on a desk or the like. Inparticular, since the vibration, the display, and the sound emission areperformed continuously for a predetermined time, reliable recognition isachieved.

Here, in the electronic device 70 according to the present embodiment,in case of operation in a state of being placed on a desk or the like,both of the predetermined display and the predetermined sound emissionhave been performed. However, any one alone of these may be performed.Further, the vibration, the display, and the sound emission have beenperformed continuously for a predetermined time. However, thiscontinuation for a predetermined time is not indispensable. However, itcannot be overemphasized that continuation for a predetermined timeimproves the recognition rate. Further, the time of continuation may bethe same for all of the vibration, the display, and the sound emission.Alternatively, the time of continuation may be different for each ofthese. In particular, a longer display time improves the visibility.

Further, in the electronic device 70 according to the presentembodiment, the program describing the processing shown in the flowchart of FIG. 26 has been stored in the ROM. However, the program may bestored in a storage medium such as a magnetic disc, an optical disc, amagneto-optical disc, and a flash memory and then distributed.Alternatively, the program may be saved in a server (not shown) on anetwork such as the Internet and then downloaded through atelecommunication line.

Embodiment 4

FIG. 27 is a block diagram showing an outline configuration of anelectronic device according to Embodiment 4 of the present invention.Here, the electronic device 150 according to the present embodiment is aportable wireless device referred to as a smart phone similar to theelectronic device 1 according to Embodiment 1, the electronic device 40according to Embodiment 2, and the electronic device 70 according toEmbodiment 3 described above. Thus, the outline is similar to these andhence an outline diagram is omitted. Then, FIG. 1 is referred to whennecessary in description.

In FIG. 27, the electronic device 150 according to the presentembodiment includes a touch panel module 73, a Display unit 75, a devicecontrol unit 151, shield grounds 152 and 153, and variable resistors 154and 155. The touch panel module 73 includes a Touch panel unit (a touchpanel) 77 and a touch panel controller 78 for exchanging a transmissionsignal and a receiving signal with the Touch panel unit 77. The Displayunit (a display device) 75 includes an LCD, an organic EL, or anelectronic paper and thereby performs display for the purpose ofoperation of the electronic device 150 and display of an image or thelike.

The device control unit 151 performs processing (i.e., exchange of acoordinate signal with the touch panel controller 78 and provision of adisplay signal to the Display unit 75) similar to that of the devicecontrol unit 9 of the electronic device 1 according to Embodiment 1described above. Further, in addition to this basic processing, thedevice control unit 151 performs the processing of suppressing, by wayof varying the impedances of the shield grounds 152 and 153, malfunctionthat could be caused by the hand at the time of hovering operation. Asmeans for executing such processing, the device control unit 151includes: a coordinate processing unit 160 for exchanging a coordinatesignal with the touch panel controller 78 and then performing coordinateprocessing; a display processing unit 161 for providing a display signalto the Display unit 75; and a holding hand detection unit 162 fordetecting the user's holding hand for the electronic device 150 and thenswitching the resistances of the variable resistors 154 and 155.

The shield grounds 152 and 153 are provided on two opposite sides in theTouch panel unit 77. FIG. 28 is a perspective view showing the fixingpositions of the shield grounds 152 and 153 and connection between theshield grounds 152 and 153 and the variable resistors 154 and 155. Inthis figure, the shield grounds 152 and 153 are provided on opposite twosides 170 and 171 in the touch panel unit 79. That is, the shield ground(the first conductive member) 152 is provided on one (a first side) 170of the two sides in the longitudinal direction of the touch panel unit79 formed in a rectangular shape. Further, the shield ground (a secondconductive member) 153 is provided on the other (a second side) 171 ofthe two sides.

The shield ground 152 is connected to one end of the variable resistor(the first variable resistor) 154 and the shield ground 153 is connectedto one end of the variable resistor (the second variable resistor) 155.Each of the other ends of the variable resistors 154 and 155 iselectrically connected to a predetermined potential. In the presentembodiment, the predetermined potential is set to be a potential (aground potential) in a ground pattern on the circuit board 175. Wheneach of the other ends of the variable resistors 154 and 155 is groundedto the same ground as the touch panel controller 78, stabilization ofoperation is achieved.

FIG. 29 is a diagram showing the cross section of a part where theshield ground 153 is arranged in the housing 2. In this figure, theshield ground 153 has a cross section of a shape pinching the peripheraledge parts of the Display unit 75 and the Touch panel unit 77 from upand down. The shield ground 153 is arranged in the inside of the housing2 in order that a person's finger should not touch directly. Similarlyto the shield ground 153, the shield ground 152 also has a cross sectionof a shape pinching the peripheral edge parts of the Display unit 75 andthe Touch panel unit 77 from up and down and is arranged in the insideof the housing 2.

When the shield grounds 152 and 153 are provided in the Touch panel unit77, the parts where these are provided and their peripheries can beshielded individually. Then, the degree of the shielding in the partswhere the shield grounds 152 and 153 are provided and the peripheries ofthese parts varies depending on the resistances of the variableresistors 154 and 155. Then, the degree of the shielding increases withdecreasing resistance of each of the variable resistors 154 and 155 sothat the sensitivity becomes small in each of the parts where the shieldgrounds 152 and 153 are provided and the peripheries of these parts.Thus, when the part of the Touch panel unit 77 where the shield grounds152 and 153 are provided is grasped with the hand, the resistance ofeach of the variable resistors 154 and 155 is reduced so that theinfluence from the hand can be suppressed.

Here, in FIG. 29, the touch panel controller 78 is arranged immediatelyunder the Display unit 75. The Touch panel unit 77 includes anapproaching touch panel sensor 771, a protection glass 772, adhesive773, and a scattering prevention film 774.

The device control unit 151 and the touch panel controller 78 areconstructed from a CPU, a ROM, a RAM, and an interface circuit. The ROMstores a program for controlling the CPU. The RAM is used in theoperation of the CPU.

Returning to FIG. 27, on the basis of the coordinate signal obtained bythe approaching detection by the touch panel module 73, the holding-handdetection unit 162 judges whether the electronic device 150 is graspedby the user. In this case, when the user grasps the electronic device150, a coordinate signal of the peripheral edge part of the Touch panelunit 77 is outputted from the touch panel controller 78. Then, theholding hand detection unit 162 receives this coordinate signal andthereby judges that the electronic device 150 is grasped by the user.

FIG. 30 is a diagram showing an example of the method of detecting aholding-hand state. In this figure, detection of a holding-hand statecan be achieved by using an acceleration sensor in place of theapproaching detection by the touch panel module 73. The approachingdetection by the touch panel module 73 is based on a capacitance change.When a capacitance change caused by contact of the finger occurssymmetrically in left and right, two-hand operation is concluded. Whenthe capacitance on the left side is greater than the capacitance on theright side, left hand operation is concluded. When the capacitance onthe right side is greater than the capacitance on the left side, righthand operation is concluded. When no capacitance change occurs in leftand right, being placed is concluded.

When judging that the electronic device 150 is grasped by the user, theholding hand detection unit 162 sets up the resistances of the variableresistors 154 and 155. FIG. 31 is a diagram showing an example of theholding-hand state (i.e., the grasping state) of the electronic device150 and the resistances of the variable resistors 154 and 155. In thisfigure, in the case of two-hand operation, the variable resistors 154and 155 are individually set to be 1 MΩ. In the case of left handoperation, the variable resistor 154 is set to be 0Ω and the variableresistor 155 is set to be 1 MΩ. In the case of right hand operation, thevariable resistor 154 is set to be 1 MΩ and the variable resistor 155 isset to be 0Ω. In the case of being placed (when the electronic device150 is not grasped and is placed on a desk or the like), the variableresistors 154 and 155 are set to be a high impedance.

When the resistances of the variable resistors 154 and 155 are setsmall, the shield grounds 152 and 153 become close to the ground level.Thus, the shielding effect increases and hence the response of the Touchpanel unit 77 becomes low. That is, when the resistances of the variableresistors 154 and 155 are set small, the shielding effect by the shieldgrounds 152 and 153 increases and hence the hovering distance (adistance between the Touch panel unit 77 and the finger) becomes short.

In the case of left hand operation, since the left thumb affects theTouch panel unit 77, the resistance of the variable resistor 154 on theleft side is set small (e.g., 0Ω) in order that the hovering distance ofthe left part of the Touch panel unit 77 is suppressed. That is, theresponse of the left part of the Touch panel unit 77 is lowered. In thevariable resistor 155 on the right side, the resistance is set to bemiddle (e.g., 1 MΩ) in order that operation with the left thumb tip partis allowed to a certain extent. In the case of right hand operation,since the right thumb affects the Touch panel unit 77, the resistance ofthe variable resistor 155 on the right side is set small (e.g., 0Ω) inorder that the hovering distance of the right part of the Touch panelunit 77 is suppressed. That is, the response of the right part of theTouch panel unit 77 is lowered. In the variable resistor 154 on the leftside, the resistance is set to be middle (e.g., 1 MΩ) in order thatoperation with the right thumb tip part is allowed to a certain extent.In the case of two-hand operation, the resistances of the variableresistors 154 and 155 on both sides are individually set to be middle(e.g., 1 MΩ) so that the influence caused by grasping of the electronicdevice 150 is avoided. In the case of being placed, no influence iscaused by the finger grasping the electronic device 150. Thus, theresistances of the variable resistors 154 and 155 on both sides areindividually set to be a high impedance so that the hovering distance isincreased in the shield grounds 152 and 153 and their periphery.

Preferably, the resistances of the variable resistors 154 and 155 invarious modes of holding hand are set up as follows.

(1) In a predetermined operation state, the resistance of the variableresistor 154 is set to be a first resistance and the resistance of thevariable resistor 155 is set to be a second resistance greater than thefirst resistance.

This is an operation state that the electronic device 150 is graspedwith the right hand and then the Touch panel unit 77 is operated withthe thumb or the like of the right hand or alternatively an operationstate that the electronic device 150 is grasped with the left hand andthen the Touch panel unit 77 is operated with the thumb or the like ofthe left hand. The first resistance is “small” and may be 0Ω. The secondresistance is “medium” and is, for example, 1 MΩ.

(2) The predetermined operation state is adopted as a first operationstate. Then, in a second operation state, the resistance of the variableresistor 154 is set to be the second resistance and the resistance ofthe variable resistor 155 is set to be the first resistance.

In response to switching of the operation state between the firstoperation state and the second operation state, the resistances of thevariable resistor 154 and the variable resistor 155 are changed andhence the influence to the Touch panel unit 77 can be suppressed inwhichever of the first and the second operation states. Here, at thetime that the resistance of the variable resistor 154 is set to be thesecond resistance, slight deviation from the second resistance isallowed. Further, at the time that the resistance of the variableresistor 155 is set to be the first resistance, slight deviation fromthe first resistance is allowed.

(3) The predetermined operation state is adopted as a first operationstate. Then, in a second operation state, the resistance of the variableresistor 154 is set to be a third resistance and the resistance of thevariable resistor 155 is set to be a fourth resistance smaller than thethird resistance.

The third resistance is “medium” and is, for example, 1.1 MΩ. Here, thesecond resistance and the third resistance may be substantially the sameresistance. Further, the fourth resistance is “small” and is, forexample, 0.1 MΩ. Here, the first resistance and the fourth resistancemay be substantially the same resistance.

(4) The predetermined operation state is adopted as a first operationstate. Then, in a third operation state, the resistance of the variableresistor 154 and the resistance of the variable resistor 155 are set tobe the second resistance.

This is an operation state that the electronic device 150 is graspedwith the right hand and then the Touch panel unit 77 is operated withthe left hand or alternatively the reverse operation state to this.

(5) This is a variation of (4). The predetermined operation state isadopted as a first operation state. Then, in a third operation state,the resistance of the variable resistor 154 is set to be a fifthresistance and the resistance of the variable resistor 155 is set to bea sixth resistance that is a predetermined magnification of the fifthresistance.

The fifth resistance is, for example, 0.9 MΩ and the sixth resistanceis, for example, 0.98 MΩ. Thus, these are substantially the same as thesecond resistance. However, a slight difference is expected and,obviously, the fifth resistance and the sixth resistance areindividually greater than the first resistance. For example, thepredetermined magnification is a value between 0.5 and 2.

(6) In a fourth operation state, the resistance of the variable resistor154 is set to be a seventh resistance greater than at least the secondresistance and the resistance of the variable resistor 155 is set to bethe seventh resistance.

This is for a placed state. The seventh resistance includes also “large”which is a high impedance (blocking).

The magnitude relations between the second resistance, the thirdresistance, the fourth resistance, the fifth resistance, the sixthresistance, and the seventh resistance described above are such that thesecond resistance<the seventh resistance, the third resistance<theseventh resistance, the fourth resistance<the seventh resistance, thefifth resistance<the seventh resistance, and the sixth resistance<theseventh resistance.

A slight deviation from the seventh resistance is allowed as long as theimpedance is as high as being recognizable as a high impedance.

(7) In a fourth operation state, the resistance of the variable resistor154 is set to be the seventh resistance greater than at least the secondresistance and the resistance of the variable resistor 155 is set to bean eighth resistance greater than at least the second resistance.

The seventh and the eighth resistances are “large” and are, for example,10 GΩ. The magnitude relations between the second resistance, the thirdresistance, the fourth resistance, the fifth resistance, the sixthresistance, and the eighth resistance described above are such that thesecond resistance<the eighth resistance, the third resistance<the eighthresistance, the fourth resistance<the eighth resistance, the fifthresistance<the eighth resistance, and the sixth resistance<the eighthresistance.

Next, the operation of the electronic device 150 according to thepresent embodiment is described below.

FIG. 32 is a flow chart showing the holding-hand detection processing ofthe electronic device 150 according to the present embodiment. Thepresent processing is performed during the time that the display of theelectronic device 150 is in an ON state. Specifically, this processingis performed during the time after the power is turned ON and hence thedisplay becomes ON until the power saving mode is started so that thedisplay becomes OFF. The ON-OFF control of the display is premised to beperformed by the display processing unit 161.

In FIG. 32, first, the display processing unit 161 turns ON the display(step S50). After the display ON, the holding hand detection unit 162detects the holding-hand state (step S51) and then judges whether themode is the two-hand operation mode (step S52). In case of the two-handoperation mode (when “Yes” is concluded in the judgment at step S52),the holding hand detection unit 162 sets each of the variable resistors154 and 155 to be 1 MΩ (step S53). After the holding hand detection unit162 has set each of the variable resistors 154 and 155 to be 1 MΩ, thedisplay processing unit 161 judges whether the state is display OFF(step S54). When the state is display OFF, the present processing isterminated. When the state is not display OFF, the procedure returns tostep S51.

In the judgment at step S52, when having judged as not being thetwo-hand operation mode (when “No” is concluded in the judgment at stepS52), the holding hand detection unit 162 judges whether the mode is theleft hand operation mode (step S55). In case of the left hand operationmode (when “Yes” is concluded in the judgment at step S55), the holdinghand detection unit 162 sets the variable resistor 154 to be 0Ω and setsthe variable resistor 155 to be 1 MΩ(step S56). After the variableresistor 154 is set to be 0Ω and then the variable resistor 155 is setto be 1 MΩ, the display processing unit 161 judges whether the state isdisplay OFF (step S54). When the state is display OFF, the presentprocessing is terminated. When the state is not display OFF, theprocedure returns to step S51.

In the judgment at step S55, when having judged as not being the lefthand operation mode (when “No” is concluded in the judgment at stepS55), the holding hand detection unit 162 judges whether the mode is theright hand operation mode (step S57). In case of the right handoperation mode (when “Yes” is concluded in the judgment at step S57),the holding hand detection unit 162 sets the variable resistor 154 to be1 MΩ and sets the variable resistor 155 to be 0Ω (step S58). After thevariable resistor 154 is set to be 1 MΩ and then the variable resistor155 is set to be 0Ω, the display processing unit 161 judges whether thestate is display OFF (step S54). When the state is display OFF, thepresent processing is terminated. When the state is not display OFF, theprocedure returns to step S51.

In the judgment at step S57, when having judged as not being the righthand operation mode (when “No” is concluded in the judgment at stepS57), the holding hand detection unit 162 judges as being placed (stepS59) and then sets each of the variable resistors 154 and 155 to be ahigh impedance largely exceeding 1 MΩ (step S60). After the holding handdetection unit 162 has set each of the variable resistors 154 and 155 tobe the high impedance, the display processing unit 161 judges whetherthe state is display OFF (step S54). When the state is display OFF, thepresent processing is terminated. When the state is not display OFF, theprocedure returns to step S51.

As such, according to the electronic device 150 according to the presentembodiment, the electronic device includes: the shield grounds 152 and153 provided on two opposite sides 170 and 171 in the longitudinaldirection of the Touch panel unit 77 having a rectangular shape overlaidon the Display unit 75; the variable resistor 154 whose one end isconnected to the shield ground 152 and whose the other end is connectedto the ground pattern on the circuit hoard 175; the variable resistor155 whose one end is connected to the shield ground 153 and whose theother end is connected to the ground pattern on the circuit board 175;and the holding hand detection unit 162 that, on the basis of thecoordinate signal obtained by the approaching detection by the touchpanel module 73, judges whether the electronic device 150 is grasped bythe user and that, when the electronic device 150 is grasped by theuser, sets up the resistances of the variable resistors 154 and 155.Then, the holding hand detection unit 162 sets each resistance of thevariable resistors 154 and 155 to be “medium” in the case of two-handoperation, sets the resistance of the variable resistor 154 to be“small” and the resistance of the variable resistor 155 to be “medium”in the case of left hand operation, sets the resistance of the variableresistor 154 to be “medium” and the resistance of the variable resistor155 to be “small” in the case of right hand operation, and setting eachresistance of the variable resistors 154 and 155 to be the “highimpedance” in the case of being placed. Thus, the influence caused bythe hand in the electronic device 150 (i.e., malfunction caused by aresponse of the Touch panel unit 77) can be suppressed.

Here, in the electronic device 150 according to the present embodiment,the program describing the processing shown in the flow chart of FIG. 32has been stored in the ROM. However, the program may be stored in astorage medium such as a magnetic disc, an optical disc, amagneto-optical disc, and a flash memory and then distributed.Alternatively, the program may be saved in a server (not shown) on anetwork such as the Internet and then downloaded through atelecommunication line.

FIG. 33 is a block diagram showing an outline configuration of anelectronic device 156 which detects a holding-hand state by using anacceleration sensor. Here, in this figure, like parts to those of FIG.27 are designated by like numerals and hence their description isomitted. The electronic device 156 which detects a holding-hand state onthe basis of the acceleration includes a device control unit 157provided with an acceleration detection unit 163. The device controlunit 157 includes the coordinate processing unit 160, the displayprocessing unit 161, the acceleration detection unit 163, and a holdinghand detection unit 164. The acceleration detection unit 163 includes anacceleration sensor (not shown) and outputs to the holding handdetection unit 164 the acceleration detected by the acceleration sensor.As for the holding-hand state detection using the acceleration sensor,FIG. 30 described above should be referred to. The holding handdetection unit 164 detects the user's holding hand for the electronicdevice 150 on the basis of the output from the acceleration detectionunit 163 and then switches the resistances of the variable resistors 154and 155. Setting of the resistances of the variable resistors 154 and155 in various modes of holding hand is as described above.

Embodiment 5

FIG. 34 is a front view showing an outline of an electronic deviceaccording to Embodiment 5 of the present invention. In this figure, theelectronic device 200 according to the present embodiment is a portablewireless device referred to as a smart phone similar to the electronicdevice 1 according to Embodiment 1 described above. Then, a receiver 202is provided in an upper part on the front face side of a housing 201formed in a quadrangular shape, and a touch panel module (correspondingto a touch panel) 203 of capacitive sensing type is provided under thereceiver 202. Further, three function buttons 204-1 to 204-3 areprovided under the touch panel module 203.

FIG. 35 is a block diagram showing an outline configuration of theelectronic device 200 according to the present embodiment. In thisfigure, the electronic device 200 according to the present embodimentincludes the touch panel module 203 described above, a Display unit(corresponding to a display device) 205, and a device control unit 206.The touch panel module 203 includes a Touch panel unit 207 and a touchpanel controller 208 for exchanging a transmission signal and areceiving signal with the Touch panel unit 207. The device control unit206 exchanges with the touch panel module 203 a coordinate signalindicating the position of the instructing body and provides a displaysignal to the Display unit 205. Here, the Display unit 205 and the touchpanel module 203 constitute a touch panel unit 209. The device controlunit 206 includes a CPU (Central Processing Unit), a ROM (Read OnlyMemory), a RAM (Random Access Memory), and an interface circuit (all notshown). The ROM stores a program for controlling the CPU. The RAM isused in the operation of the CPU.

The Display unit 205 has a quadrangular shape and is used for displayfor the purpose of operation of the electronic device 200 according tothe present embodiment and for display of an image or the like. In theDisplay unit 205, an LCD (Liquid Crystal Display), an organic EL(Electro Luminescence), or an electronic paper is employed. The touchpanel module 203 employs a capacitive sensing type that allows operation(“hovering operation”) at a height within a predetermined range withoutthe necessity of touching the touch panel surface with a fingertip.

The Touch panel unit 207 has a quadrangular shape approximately the sameas the Display unit 205 and is overlaid on the Display unit 205. Here,the Display unit 205 and the Touch panel unit 207 may be arranged in theinside of the housing 201 or alternatively in the outside. However, inwhichever case, the Touch panel unit 207 is arranged on the outer siderelative to the Display unit 205. Further, in the electronic device 200according to the present embodiment, the shape of the Display unit 205and the Touch panel unit 207 is set to be quadrangular. However, theshape may be rectangular or square.

The Touch panel unit 207 includes transmission electrodes and receivingelectrodes (not illustrated), which are arranged in a manner of beingseparated from each other on the lower surface of a plate-shapeddielectric material. A driving pulse based on the transmission signaloutputted from the touch panel controller 208 is applied on thetransmission electrode. When the driving pulse is applied on thetransmission electrode, an electric field is generated from thetransmission electrode. When an instructing body (a finger, a pen, orthe like; a “finger” is premised in the present embodiment) enters thiselectric field, the number of lines of electric force between thetransmission electrode and the receiving electrode decreases. The changein the number of lines of electric force appears as a change in theelectric charge on the receiving electrode. A receiving signalcorresponding to a change in the electric charge on the receivingelectrode is outputted to the touch panel controller 208. The touchpanel controller 208 exchanges a control signal with the device controlunit 206 and outputs a transmission signal to the Touch panel unit 207.Further, the touch panel controller 208 receives the receiving signaloutputted from the Touch panel unit 207 so as to detect the finger fromthe inputted receiving signal and then outputs a coordinate signalindicating the position (X,Y,Z) of the detected finger to the devicecontrol unit 206.

FIG. 36 is a diagram showing a method of detecting a finger in the touchpanel controller 208. In this figure, when the distance corresponding tothe level of the receiving signal outputted from the Touch panel unit207 (i.e., the distance from the Touch panel unit 207 to the fingertip60) Za falls between the first distance Z0 and the second distance Z1,the touch panel controller 208 detects the fingertip 60. At that time,with taking into consideration the blur of the fingertip 60, thedistance is calculated as the average within a predetermined time. FIG.37 is a diagram showing a time-dependent change in the distance betweenthe fingertip 60 and the Touch panel unit 207. As shown in the figure,between the first distance Z0 and the second distance Z1, the average ofthe distance is calculated between time t1 and time t2. When thisaverage of the distance falls between the first distance Z0 and thesecond distance Z1, the fingertip 60 is detected.

Returning to FIG. 35, the device control unit 206 acquires thecoordinate signal outputted from the touch panel controller 208 and thenperforms various processing such as character input processing andcharacter display processing. The result of the character displayprocessing is outputted as a display signal to the Display unit 205.FIG. 34 shows a mail screen at the time that an application forgenerating an E-mail is started. This mail screen contains a destinationinput display region 300, a subject input display region 301, and aninput display region 302. These display regions 300 to 302 are set up inthe Touch panel unit 207. Here, the display position of the inputdisplay region 302 may be fixed or alternatively variable.

The Display unit 205 displays ten keys 451, a cursor key 452, andcharacters (“kana characters”, “alphabetical characters”, or “numericcharacters”) inputted through the ten keys 451. The cursor key 452displays the kind of input character and is displayed at the upper leftcorner of the Display unit 205. Here, the cursor key 452 corresponds tothe predetermined region of the Display unit 205. Further, the cursorkey 452 is an icon. When icon display is employed for the cursor key452, operability improvement in character input is achieved.

The ten keys 451 displays, in the form of ten keys, input charactercandidates serving as information relevant to the cursor key 452 and aredisplayed near the cursor key 452. FIG. 34 shows the ten keys 451 of acase that “kana character” is selected as the kind of input character.Thus. “a, ka, sa, ta, . . . ” are displayed as input charactercandidates. Regions corresponding to each of the cursor key 452 and theten keys 451 are also set up in the Touch panel unit 207. When theregion corresponding to the cursor key 452 of the Touch panel unit 207is touched by the fingertip 60, selection of the kind of input charactercan be performed. After the selection of the kind of input character,when the fingertip 60 is moved in the immediately upward direction ofthe cursor key 452, the ten keys 451 are displayed. In this case, asdescribed above, the ten keys 451 are displayed near the cursor key 452.When input character candidates are displayed in the form of ten keys,operability improvement in character input is achieved.

FIG. 38 is a diagram showing operation from selection of the kind ofinput character in the electronic device 200 according to the presentembodiment to selection of the ten-key size. Further, FIG. 39 is a flowchart showing the procedure of selection operation for the kind of inputcharacter and selection operation for the ten-key size in the electronicdevice 200 according to the present embodiment. In FIGS. 38 and 39, whenthe fingertip 60 touches the cursor key 452 (step S70), the kinds ofinput character such as “kana”, “alphabetical character”, and “numericcharacter” are displayed. In this state, the fingertip 60 is moved in ahorizontal direction and then touching is performed, a desired kind ofinput character can be selected (step S71). The kinds of input charactersuch as “kana”, “alphabetical character”, and “numeric character” aredisplayed in the immediate vicinity of the cursor key 452. After theselection of the desired kind of input character, when the fingertip 60is brought apart in the immediately upward direction of the cursor key452, first, the ten keys 451 of standard size are displayed near thecursor key 452 (step S72). After that, when the fingertip 60 is broughtapart further so that the distance Z between the Touch panel unit 207and the fingertip 60 exceeds the distance Za, display is switched fromthe ten keys 451 of standard size to the ten keys 451 of enlarged size(step S73).

The ten keys 451 of enlarged size is continued up to the distance Zb.That is, immediately above the cursor key 452, when the distance Zbetween the Touch panel unit 207 and the fingertip 60 falls within therange of O<Z≦Za, the ten keys 451 of standard size are displayed. Incase of falling within the range of Za<Z≦Zb, the ten keys 451 ofenlarged size are displayed. As such, when the fingertip 60 is broughtapart in the immediately upward direction of the cursor key 452, thesize of the ten keys 451 varies in two steps. After being brought apartfrom the cursor key 452, when the fingertip 60 is brought close, displayis switched from the ten keys 451 of enlarged size to the ten keys 451of standard size. That is, in response to the up and down movement ofthe fingertip 60, the size of the ten keys 451 is switched from theenlarged to the standard and from the standard to the enlarged. When themeans of changing the size of the ten keys 451 is provided, informationin the desired size is easily selected and hence operability improvementin character input is achieved.

Here, after the fingertip 60 is brought apart from the cursor key 452,the fingertip 60 need not be moved accurately in the immediately upwarddirection of the cursor key 452 and hence deviation is allowed. That is,the fingertip 60 need not be contained in the region of the cursor key452.

FIG. 40 is a diagram showing operation from selection of the kind ofinput character to character input in the electronic device 200according to the present embodiment. In this figure, the operation fromselection of the kind of input character to selection of the ten-keysize is as described above and hence its description is omitted. Thus,operation after the ten-key size selection is described below. Here, theselection processing for the kind of input character is referred to asmode [1] and the selection processing for ten-key size is referred to asmode [2]. Further, in mode [2], when the “return” key in the ten keys451 is touched, the procedure returns to mode [1] and hence selection ofthe kind of input character is allowed again.

Mode [3] that follows mode [2] is the processing of fixing the size ofthe ten keys 451. FIG. 40 shows a state that kana character is selected.In a state that the cursor key 452 selecting the kana character is seenbelow, when the fingertip 60 is moved in a horizontal direction, thesize of the ten keys 451 is fixed. In this case, in a state that the tenkeys 451 of standard size are selected, when the fingertip 60 is movedin a horizontal direction, the ten keys 451 of standard size are fixed.Further, in a state that the ten keys 451 of enlarged size are selected,when the fingertip 60 is moved in a horizontal direction, the ten keys451 of enlarged size are fixed. After the size of the ten keys 451 isfixed as such, character input is performed through the ten keys 451.The processing of character input is referred to as mode [4]. When themeans of fixing the size of the ten keys 451, operability improvement incharacter input is achieved.

In mode [4], for example, a character “na” of the ten keys 451 istouched by the fingertip 60, display of the ten keys 451 temporarilydisappears and the character string (“na”, “ni”, “nu”, “ne”, “no”) of“na” row is displayed in the periphery around the touch position. In thestate that the character string of “na” row is displayed, when a desiredcharacter (e.g., “nu”) is touched, input of this character isdetermined. The determined character is displayed in the input displayregion 302. When additional another character is to be inputted, similaroperation is performed. For example, when a character “ma” is to beinputted, when the fingertip 60 is brought apart from the character“nu”, the ten keys 451 appear. Thus, the character “ma” in the ten keys451 is touched. Then, display of the ten keys 451 temporarily disappearsand the character string (“ma”, “mi”, “mu”, “me”, “mo”) of “ma” row isdisplayed in the periphery around the touch position. In the state thatthe character string of “ma” row is displayed, when the desiredcharacter (e.g., “ma”) is touched, input of this character is determinedand hence this character is displayed in the input display region 302.Character input is achieved as such.

FIG. 41 is a flow chart showing the character input processing of theelectronic device 200 according to the present embodiment. The presentprocessing is performed mainly in the device control unit 206. In thisfigure, when character input is started (step S80), the device controlunit 206 judges whether the cursor key 452 is touched by the fingertip60 (step S81). When the cursor key 452 is not touched by the fingertip60 (i.e., when “NO” is concluded in the judgment at step S80), thepresent judgment is repeated until the cursor key 452 is touched by thefingertip 60. In contrast, when the cursor key 452 is touched by thefingertip 60 (i.e., when “YES” is concluded in the judgment at stepS80), the kind of input character is selected (step S82). That is, thekind of input character specified by the user is selected from among“kana character”, “alphabetical character”, and “numeric character”. Inthis case, which kind of input character has been specified is judged onthe basis of the coordinate signal outputted from the touch panelcontroller 208.

After the selection the kind of input character, the device control unit206 judges whether the fingertip 60 has been brought apart from thecursor key 452 (step S83). When the fingertip 60 is not brought apartfrom the cursor key 452 (i.e., when “NO” is concluded in the judgment atstep S83), the present judgment is repeated until the fingertip 60 isbrought apart from the cursor key 452. In contrast, when the fingertip60 is brought apart from the cursor key 452 (i.e., when “YES” isconcluded in the judgment at step S83), it is judged whether thedistance Z from the cursor key 452 to the fingertip 60 satisfies 0<Z≦Za(step S84). That is, the device control unit 206 acquires the distance Zfrom the cursor key 452 to the fingertip 60 on the basis of the signalvalue of the Z-coordinate of the coordinate signal outputted from thetouch panel controller 208 and then performs distance judgment. In thisjudgment, when the distance Z satisfies 0<Z≦Za (i.e., when “YES” isconcluded in the judgment at step S84, a display signal for displayingthe ten keys 451 of standard size is outputted to the Display unit 205(step S85). In contrast, when the distance Z does not satisfy 0<Z≦Za(i.e., when “No” is concluded in the judgment at step S84), it is judgedwhether the distance Z from the cursor key 452 to the fingertip 60satisfies Za<Z≦Zb (step S86). In this judgment, when the distance Z doesnot satisfy Za<Z≦Zb (i.e., when “NO” is concluded in the judgment atstep S86, the procedure returns to step S84 described above. Incontrast, when the distance Z satisfies Za<Z≦Zb (i.e., when “YES” isconcluded in the judgment at step S86, a display signal for displayingthe ten keys 451 of enlarged size is outputted to the Display unit 205(step S87).

In case that the processing of displaying the ten keys 451 of standardsize has been performed, after this processing, the device control unit206 judges whether the fingertip 60 has slid from the cursor key 452 tothe ten keys 451 (step S88). In this judgment, in case of not havingslid to the ten keys 451 (i.e., when “NO” is concluded in the judgmentat step S88), the present judgment is repeated until sliding to the tenkeys 451 is performed. In contrast, when the fingertip 60 has slid tothe ten keys 451 (i.e., when “YES” is concluded in the judgment at stepS88), the processing at step S90 is performed.

Further, in case that the processing of displaying the ten keys 451 ofenlarged size has been performed, after this processing, the devicecontrol unit 206 judges whether the fingertip 60 has slid from thecursor key 452 to the ten keys 451 (step S89). In this judgment, in caseof not having slid to the ten keys 451 (i.e., when “NO” is concluded inthe judgment at step S89), the present judgment is repeated untilsliding to the ten keys 451 is performed. In contrast, when thefingertip 60 has slid to the ten keys 451 (i.e., when “YES” is concludedin the judgment at step S89), the processing at step S90 is performed.

At step S90, it is judged whether the “return” key of the ten keys 451has been touched. In this judgment, when the “return” key of the tenkeys 451 has been touched (i.e., when “YES” is concluded in the judgmentat step S90), the procedure returns to step S82 so that the processingat and after step S82 is performed. In contrast, when the “return” keyof the ten keys 451 is not touched (i.e., when “NO” is concluded in thejudgment at step S90, the size of the ten keys 451 is fixed (step S91).That is, the ten keys 451 are fixed to the standard size or the enlargedsize.

After fixing the size of the ten keys 451, the device control unit 206performs flick input processing (step S92). That is, character input isperformed in response to flick operation by the user. For example, whenthe user performs kana character setting, then selects the “na” row, andthen selects “nu”, character input of “nu” is performed. After thecharacter input, the device control unit 206 confirms this character(step S93). Then, it is judged whether flick input is to be terminated(step S94). When flick input is not to be terminated (i.e., when “NO” isconcluded in the judgment at step S94), the procedure returns to stepS92 and then flick input processing is performed again. In contrast,when flick input is to be terminated (i.e., when “YES” is concluded inthe judgment at step S94), the present processing is terminated.

As such, according to the electronic device 200 according to the presentembodiment, the Display unit 205 displays: the cursor key 452 fordisplaying the kind of input character; and the ten keys 451 fordisplaying input character candidates in the form of ten keys near thecursor key 452. Then, the ten keys 451 are displayed when after thefingertip 60 has touched the cursor key 452, the fingertip 60 is broughtapart from the cursor key 452. Further, when the distance Z between theTouch panel unit 207 and the fingertip 60 satisfies 0<Z≦Za, the ten keys451 are displayed in the standard size. When the distance Z satisfiesZa<Z≦Zb, the ten keys 451 are displayed in the enlarged size. Thus, theten keys 451 of desired size can be selected arbitrarily and henceoperability improvement in character input is achieved. Further, theDisplay unit 205 displays the ten keys 451 and the character inputtedthrough the ten keys 451. Thus, sight line movement for character inputand displayed character check is reduced and hence operabilityimprovement in character input is achieved.

Here, in the electronic device 200 according to the present embodiment,a plurality of characters serving as input character candidates havebeen displayed in the form of ten keys. Instead, one character alone maybe displayed.

Further, in the electronic device 200 according to the presentembodiment, the size of information has been changed such that the sizeof the ten keys 451 is changed in accordance with the distance betweenthe Touch panel unit 207 and the fingertip 60. Instead, the informationitself may be changed. For example, “a, i, u, e, o” may be changed into“ka, ki, ku, ke, ko”.

Further, in the electronic device 200 according to the presentembodiment, in its operation, touching the ten keys 451 and the cursorkey 452 is premised (i.e., contact is used as a trigger). However,approaching to an extent that can be regarded as touching may beincluded. For example, the ten keys 451 have been displayed when afterthe fingertip 60 has touched the cursor key 452, the fingertip 60 isbrought apart from the cursor key 452. However, the ten keys 451 may bedisplayed when after the fingertip 60 approaches the cursor key 452 toan extent that can be regarded as touching, the fingertip 60 is broughtapart from the cursor key 452.

Further, the electronic device 200 according to the present embodimenthas been a portable wireless device referred to as a smart phone,however, is not limited to an electronic device of this kind. That is, agame machine, a television receiver, a microwave oven, a washingmachine, a refrigerator, a car navigation device, a car provided with acar navigation device, a home energy management system (HEMS) terminaldevice, a house provided with a home energy management system (HEMS)terminal device, an ATM (Automated Teller Machine), and the like may beemployed.

Further, in the electronic device 200 according to the presentembodiment, the program describing the processing shown in the flowchart of FIG. 41 has been stored in the ROM. However, the program may bestored in a storage medium such as a magnetic disc, an optical disc, amagneto-optical disc, and a flash memory and then distributed.Alternatively, the program may be saved in a server (not shown) on anetwork such as the Internet and then downloaded through atelecommunication line.

The present invention has been described in detail with reference toparticular embodiments. However, it is clear for the person skilled inthe art that various modifications and corrections can be made withoutdeparting from the spirit and the scope of the present invention.

This application is based on a Japanese patent application (JapanesePatent Application No. 2011-276175) filed on Dec. 16, 2011, a Japanesepatent application (Japanese Patent Application No. 2012-074721) filedon Mar. 28, 2012, a Japanese patent application (Japanese PatentApplication No. 2012-085750) filed on Apr. 4, 2012, a Japanese patentapplication (Japanese Patent Application No. 2012-095879) filed on Apr.19, 2012, and a Japanese patent application (Japanese Patent ApplicationNo. 2012-127290) filed on Jun. 4, 2012. The contents of which areincorporated herein by reference.

INDUSTRIAL APPLICABILITY

The present invention is a touch panel of capacitive sensing type, whichhas an effect that when the device body is held, the influence of thehand to the hand-held part is suppressed and which is applicable to anelectronic device such as a smart phone employing a touch panel ofcapacitive sensing type.

DESCRIPTION OF REFERENCE NUMERALS

-   -   1 Electronic device    -   2 Housing    -   3 Receiver    -   4 Liquid crystal display unit    -   5 Touch panel unit    -   5-1 Receiving sensor panel    -   5-1 a Receiving electrode    -   5-1 b Transmission electrode    -   5-2 Transmission sensor panel    -   5-2 c Transmission electrode    -   6 Touch panel module    -   7 Touch panel unit    -   7-1 to 7-3 Function button    -   8 Touch panel controller    -   9 Device control unit    -   20 Cover panel    -   21 Back light unit    -   22 Battery unit    -   30 Display    -   40 Electronic device    -   41 Housing    -   42 Receiver    -   43 Touch panel module    -   44-1, 44-2, 44-3 Function button    -   45 Display unit    -   46 Device control unit    -   47 Touch panel unit    -   48 Touch panel controller    -   49 Touch panel unit    -   50 Destination input display region    -   51 Subject input display region    -   52 Input display region    -   53 Character kind selection key display region    -   54 Character kind selection key    -   60 Fingertip    -   531 Kana character input key display region    -   532 Numeric character input key display region    -   533 Alphabetical character input key display region    -   534 Symbol input key display region    -   535 Pictorial symbol input key display region    -   541 Kana character input key    -   542 Numeric character input key    -   543 Alphabetical character input key    -   544 Symbol input key    -   545 Pictorial symbol input key    -   550 to 569 Second display region    -   70 Electronic device    -   71 Housing    -   73 Touch panel module    -   75 Display unit    -   76 Device control unit    -   77 Touch panel unit    -   77-1 Receiving sensor panel    -   77-2 Transmission sensor panel    -   78 Touch panel controller    -   79 Touch panel unit    -   80 Grasping judgment unit    -   81 Feedback switching unit    -   82 Visual/auditory feedback unit    -   90 Vibration feedback element    -   90 a Vibrator    -   90 b Vibration actuator    -   90 c Piezo actuator    -   91 Speaker    -   701 Icon    -   702 Predetermined display    -   150 The electronic device    -   151 Device control unit    -   152, 153 Shield ground    -   154, 155 Variable resistor    -   160 Coordinate processing unit    -   161 Display processing unit    -   162 Holding-hand detection unit    -   170 First side    -   171 Second side    -   175 Circuit board    -   771 Approaching touch panel sensor    -   772 Protection glass    -   773 Adhesive    -   774 Scattering prevention film    -   200 Electronic device    -   201 Housing    -   202 Receiver    -   203 Touch panel module    -   204-1 to 204-3 Function button    -   205 Display unit    -   206 Device control unit    -   207 Touch panel unit    -   208 Touch panel controller    -   209 Touch panel unit    -   300 Destination input display region    -   301 Subject input display region    -   302 Input display region    -   451 Ten keys    -   452 Cursor key

What is claimed is:
 1. An electronic device comprising: a displaydevice; a touch panel overlaid on the display device and including atleast a predetermined side; a conductive member provided along thepredetermined side; and a variable resistor having one end which iselectrically connected to the conductive member and an other end whichis electrically connected to a predetermined potential, wherein aresistance of the variable resistor is switchable.
 2. The electronicdevice according to claim 1, wherein the predetermined side comprises afirst side, wherein the conductive member comprises a first conductivemember, wherein the touch panel includes a second side, wherein thevariable resistor comprises a first variable resistor, and wherein theelectronic device comprises: a second conductive member provided alongthe second side; and a second variable resistor having one end which iselectrically connected to the second conductive member and an other endwhich is electrically connected to the predetermined potential, whereina resistance of the first variable resistor and a resistance of thesecond variable resistor are switchable.
 3. The electronic deviceaccording to claim 2, wherein the first side and the second side areopposite to each other.
 4. The electronic device according to claim 3,wherein the touch panel is quadrangular; and wherein the first side andthe second side are opposite sides of the quadrangle.
 5. The electronicdevice according to claim 4, wherein the touch panel is rectangular; andwherein the first side and the second side are longer opposite sides ofthe rectangle.
 6. The electronic device according to claim 2, wherein atleast one of the resistance of the first variable resistor and theresistance of the second variable resistor are switched depending on anoperation state.
 7. The electronic device according to claim 6, whereinin a predetermined operation state, the resistance of the first variableresistor is set to be a first resistance and the resistance of thesecond variable resistor is set to be a second resistance greater thanthe first resistance.
 8. The electronic device according to claim 7,wherein the predetermined operation state comprises a first operationstate; and wherein in a second operation state, the resistance of thefirst variable resistor is set to be the second resistance and theresistance of the second variable resistor is set to be the firstresistance.
 9. The electronic device according to claim 7, wherein thepredetermined operation state comprises a first operation state; andwherein in a second operation state, the resistance of the firstvariable resistor is set to be a third resistance and the resistance ofthe second variable resistor is set to be a fourth resistance smallerthan the third resistance.
 10. The electronic device according to claim7, wherein the predetermined operation state comprises a first operationstate; and wherein in a third operation state, the resistance of thefirst variable resistor and the resistance of the second variableresistor are set to be the second resistance.
 11. The electronic deviceaccording to claim 7, wherein the predetermined operation statecomprises a first operation state; and wherein in a third operationstate, the resistance of the first variable resistor is set to be afifth resistance and the resistance of the second variable resistor isset to be a sixth resistance that is a predetermined magnification ofthe fifth resistance.
 12. The electronic device according to claim 8,wherein in a fourth operation state, the resistance of the firstvariable resistor is set to be a seventh resistance greater than thesecond resistance and the resistance of the second variable resistor isset to be the seventh resistance.
 13. The electronic device according toclaim 8, wherein in a fourth operation state, the resistance of thefirst variable resistor is set to be a seventh resistance greater thanthe second resistance and the resistance of the second variable resistoris set to be an eighth resistance greater than the second resistance.14. The electronic device according to claim 6, wherein the operationstate is detected on the basis of an output from the touch panel. 15.The electronic device according to claim 6, further comprising anacceleration sensor that detects an attitude of a body of the electronicdevice, wherein the operation state is detected on the basis of outputfrom the acceleration sensor.
 16. The electronic device according toclaim 1, wherein the predetermined potential is a ground potential. 17.A resistance switching method employable in an electronic deviceincluding a display device, a touch panel overlaid on the display deviceand including at least a predetermined side, a conductive memberprovided along the predetermined side, and a variable resistor havingone end which is electrically connected to the conductive member and another end which is electrically connected to a predetermined potential,the method comprising switching a resistance of the variable resistor.